JPH0637060A - Semiconductor substrate processing method - Google Patents

Abstract

(57) [Abstract] [Purpose] A first step of forming a mask layer made of a resist on a semiconductor substrate prepared in advance, and after the first step, the mask layer is masked on the semiconductor substrate. A semiconductor substrate processing method comprising: a second step of performing an etching process using a hydrocarbon-based gas plasma, and a third step of removing the mask layer from the semiconductor substrate after the second step. In the first step, even if the mask layer is formed to have a hem or a residue is left on the semiconductor substrate, the mask layer is formed in such a manner in the second step. By having a hem and not leaving such a residue on the semiconductor substrate, the semiconductor substrate can be finely and precisely etched, and the third Mask layer removed in process Easy to to. In the semiconductor substrate processing method, oxygen plasma is applied to the mask layer after the first step, before the second step, and after the second step and before the third step. Each of the steps has a different etching process.

Description

Detailed Description of the Invention

[0001]

2. Description of the Related Art The present invention relates to a semiconductor substrate having one or a plurality of semiconductor layers laminated on a semiconductor substrate body or not formed by etching treatment using a mask layer made of a resist. The present invention relates to a semiconductor substrate processing method for processing.

[0002]

2. Description of the Related Art Conventionally, the following semiconductor substrate processing method has been proposed with reference to FIG.

That is, assuming that the semiconductor substrate 1 consisting only of the semiconductor substrate body 2 made of InP, for example, is prepared in advance as a semiconductor substrate to be processed, a resist such as an electron beam resist is applied on the semiconductor substrate 1. The mask layer 11 to be formed is formed into a predetermined pattern by an exposure process using an electron beam and a subsequent development process (FIG. 6A).

Next, in a vacuum container (not shown), hydrocarbons formed by plasma of a mixed gas of, for example, ethane and hydrogen in a ratio of 1: 1 with respect to the semiconductor substrate 1 using the mask layer 11 as a mask. By performing an etching process using a system gas plasma, a groove 13 is formed in the semiconductor substrate body 2 so as to form a protrusion 12 having a pattern corresponding to the mask layer 11 (FIG. 6B). .

Next, the mask layer 11 is removed by removal from the semiconductor substrate 1 by using a liquid composed of, for example, N-methylpyrrolidone (FIG. 6C).

The above is the conventionally proposed semiconductor substrate processing method.

According to the conventional semiconductor substrate processing method described above with reference to FIG. 6, a step of etching treatment for forming the groove 13 so as to form the protrusion 12 on the semiconductor substrate body 2 (FIG. 6B).
In addition, since the plasma of the hydrocarbon gas is used, the semiconductor substrate body 2 is hardly damaged in this step, or even if the semiconductor substrate main body 2 is damaged, the damage is sufficiently small as compared with the case of using the plasma of another gas. In addition, since the etching selection ratio between the mask layer 11 and the semiconductor substrate main body 2 can be set larger than in the case where plasma of another gas is used, the protrusion 12 is formed with a small side etching amount. Therefore, the semiconductor substrate 1 can be processed with a desired pattern with high accuracy without damage.

Further, conventionally, a semiconductor substrate processing method described below with reference to FIGS. 7 and 8 has also been proposed. 7 and 8, the parts corresponding to those in FIG. 6 are designated by the same reference numerals.

That is, on the semiconductor substrate body 2 made of, for example, InP, made of, for example, InP and having a thickness of, for example, 500 nm.
A semiconductor layer 3 having a thickness of 1 nm and a semiconductor layer 4 made of, for example, InGaAs and having a thickness of, for example, 5 nm.
A semiconductor substrate 1 having a structure in which a semiconductor layer 5 made of nP and having a thickness of, for example, 80 nm and a semiconductor layer 6 made of, for example, InGaAs and having a thickness of, for example, 3 nm are laminated in that order. However, assuming that it is prepared in advance as a semiconductor substrate to be processed, a mask made of a resist such as an electron beam resist is formed on the semiconductor substrate 1 as in the case of the conventional semiconductor substrate processing method described above with reference to FIG. Exposing the layer 11 with an electron beam,
By the subsequent development processing, a predetermined pattern is formed (FIG. 7A).

Next, in a vacuum container (not shown), the semiconductor substrate 1 is subjected to an etching process using an etching solution using the mask layer 11 as a mask, so that the semiconductor layer 6 is changed to the mask layer 11. A semiconductor layer 16 having a corresponding pattern is formed (FIG. 7B).

Next, the mask layer 11 is removed by evaporation from the semiconductor substrate 1 using a solution of N-methylpyrrolidone, for example (FIG. 7C).

Next, with respect to the semiconductor substrate 1, the semiconductor layer 16
The pattern corresponding to the semiconductor layer 16 is provided from the semiconductor layer 5 by performing an etching process using an etching solution using, for example, a solution of chlorine and water in a ratio of 3: 1 as a mask. The semiconductor layer 15 is formed (FIG. 8).
D).

Next, with respect to the semiconductor substrate 1, the semiconductor layer 16
The semiconductor layer 4 is removed from the semiconductor layer 4 by performing an etching process using the semiconductor layer 15 as a mask, for example, an etching solution made of a sulfuric acid-based solution containing sulfuric acid, hydrogen peroxide, and water at a ratio of 1: 1: 20. A semiconductor layer 14 having a pattern corresponding to the layer 15 is formed (FIG. 8E). In this case, the semiconductor layer 16 is the same InGaAs as the semiconductor layer 4.
Since it is a system and has a smaller thickness than the semiconductor layer 4, it is removed from the semiconductor layer 15.

The above is another semiconductor substrate processing method that has been conventionally proposed.

According to the conventional semiconductor substrate processing method described above with reference to FIGS. 7 and 8, in the step of forming the semiconductor layer 16 from the semiconductor layer 6 by the etching process using the mask layer 11 as a mask (FIG. 7B), the semiconductor layer is formed. If 6 is formed thin (as described above, for example, a thin thickness of 3 nm),
The semiconductor layer 16 can be formed so as to conform to the pattern of the mask layer 11 with high accuracy, while the semiconductor layer 15 is formed in the step of forming the semiconductor layer 15 from the semiconductor layer 5 (FIG. 8D). Is formed by an etching process using the semiconductor layer 16 as a mask, and in the step of forming the semiconductor layer 14 from the semiconductor layer 4 (FIG. 8E), the semiconductor layer 14 is etched using the semiconductor layers 16 to 15 as a mask. Since the semiconductor layers 15 and 14 are formed by the processing, the semiconductor layers 15 and 14 can be formed with high precision according to the pattern of the mask layer 11.

[0016]

In the case of the conventional semiconductor substrate processing method described above with reference to FIG. 6, the mask layer 1 is formed on the semiconductor substrate 1.
In the step of forming 1 (FIG. 6A), the mask layer 1
1 does not have a hem as shown by reference numeral 17 and does not leave a residue (not shown) made of the material of the mask layer 11 on the semiconductor substrate body 2, but the mask layer 11 is fine. Since it becomes more difficult as it becomes, in the step of forming the groove 13 so as to form the projection 12 in the semiconductor substrate body 2 (FIG. 6B), the projection 12 is masked by the mask layer 11 as shown by the dotted line. However, there is a drawback that it is difficult to process the semiconductor substrate 1 into a desired fine pattern with high precision. Was.

Further, in the step (FIG. 6B) of forming the groove 13 in the semiconductor substrate body 2 so as to form the protrusion 12 by the etching process using the hydrocarbon-based gas plasma with the mask layer 11 as a mask, As indicated by reference numeral 18, a layer made of a carbon compound produced by polymerization of the hydrocarbon-based gas component and the material of the semiconductor substrate body 2 is formed on the mask layer 11, so that the mask layer 11 is formed. In the step of removing from the semiconductor substrate 1 (FIG. 6C), there is a drawback that it is difficult to remove the mask layer 11.

Further, in the case of the conventional semiconductor substrate processing method described above with reference to FIGS. 7 and 8, in the step of forming the mask layer 11 on the semiconductor substrate 1 (FIG. 7A), the mask layer 11 is formed.
As in the case of the conventional semiconductor substrate processing method described above with reference to FIG. 6, in the case of the conventional semiconductor substrate processing method described above with reference to FIG. A process of forming the semiconductor layer 16 from the semiconductor layer 6 is difficult because the finer the mask layer 11 is, the more difficult it is to form a residue (not shown) similar to the above (FIG. 7B). In FIG. 8, the semiconductor layer 16 is formed as one that does not correspond to the pattern of the mask layer 11 with high accuracy as shown by the dotted line, and therefore, the steps of forming the semiconductor layers 15 and 14 (FIGS. 8D and E). In these cases, they are not formed in a desired pattern as shown by the dotted line, so that it is difficult to process the semiconductor substrate 1 into a desired fine pattern with high accuracy. It had the drawback of being.

The semiconductor layer 16 is separated from the semiconductor layer 6 by
In the step (FIG. 7B) of forming by etching using the mask layer 11 as a mask, the etching is
Since the etching solution is used, the etching selection ratio between the mask layer 11 and the semiconductor layer 16 is set to the etching process for forming the groove 13 in the semiconductor substrate body 2 in the conventional semiconductor substrate processing method described above with reference to FIG. As in the case of using the hydrocarbon-based gas plasma used for the above, the size of the semiconductor layer 16 cannot be so large that the semiconductor layer 16 may be formed as side-etched. It has a drawback that it is difficult to process fine patterns with high precision.

Therefore, the present invention does not have the above-mentioned drawbacks.
It proposes a new semiconductor substrate processing method.

[0021]

The semiconductor substrate processing method according to the first invention of the present application conforms to the case of the conventional semiconductor substrate processing method described above with reference to FIG. A step of forming a mask layer made of a resist on a semiconductor substrate prepared in advance, which has a structure with or without formation, and (ii) after the step, with respect to the semiconductor substrate in a vacuum container A step of performing an etching process using a hydrocarbon-based gas plasma using the mask layer as a mask, and (iii) a step of removing the mask layer from the semiconductor substrate after the step.

However, in the semiconductor substrate processing method according to the first invention of the present application, in such a semiconductor substrate processing method, after the step of forming the mask layer on the semiconductor substrate, the semiconductor substrate is subjected to etching treatment. Before the step and after the step of performing an etching process on the semiconductor substrate and before the step of removing the mask layer from the semiconductor substrate, an etching process using oxygen plasma is performed on the mask layer in the vacuum container. And a step of applying.

The semiconductor substrate processing method according to the second invention of the present application is similar to the case of the conventional semiconductor substrate processing method described above with reference to FIGS. A step of forming a mask layer made of a resist on a semiconductor substrate prepared in advance, which has a structure in which first and second semiconductor layers having mutually different compositions are formed by laminating in that order; ii) After the step, the second semiconductor layer of the semiconductor substrate is subjected to an etching treatment using the mask layer as a mask to thereby obtain the second semiconductor layer.
Forming a third semiconductor layer having a pattern corresponding to the mask layer from the semiconductor layer of (3), (iii)
After that step, a step of removing the mask layer from the semiconductor substrate, and (iv) after that step, an etching solution using the third semiconductor layer as a mask was used for the first semiconductor layer. A step of forming a fourth semiconductor layer having a pattern corresponding to the third semiconductor layer from the first semiconductor layer by performing an etching process.

However, in the semiconductor substrate processing method according to the second invention of the present application, in such a semiconductor substrate processing method, the etching process in the step of forming the third semiconductor layer from the second semiconductor layer is performed in vacuum. In the container,
Hydrocarbon-based gas plasma is used, and after the step of forming the mask layer on the semiconductor substrate, before the step of forming the third semiconductor layer from the second semiconductor layer, and the second step. After the step of forming the third semiconductor layer from the semiconductor layer and before the step of removing the mask layer from the semiconductor layer, an etching process using oxygen plasma is performed on the mask layer in the vacuum container. Each has a step of applying.

[0025]

In the semiconductor substrate processing method according to the first invention of the present application, after the step of forming the mask layer on the semiconductor substrate, before the step of etching the semiconductor substrate and before the step of etching the semiconductor substrate. After the step and before the step of removing the mask layer from the semiconductor substrate, the conventional method described above with reference to FIG. 6 is performed, except that the mask layer is subjected to an etching process using oxygen plasma in a vacuum chamber. This is the same as the case of the semiconductor substrate processing method. Therefore, according to the case of the conventional semiconductor substrate processing method described above with reference to FIG. 6, plasma of hydrocarbon gas is used in the step of etching the semiconductor substrate. Therefore, in this process, the semiconductor substrate is hardly damaged, or even if it is damaged, it receives only a sufficiently small amount of damage as compared with the case where plasma of another gas is used. At the same time, the etching selection ratio between the mask layer and the semiconductor substrate can be made larger than that when using plasma of another gas, so that the unetched region of the semiconductor substrate has a small side etching amount. Thus, the semiconductor substrate can be processed into a desired pattern with high accuracy without damage.

However, in the case of the semiconductor substrate processing method according to the first invention of the present application, oxygen plasma is applied to the mask layer after the step of forming the mask layer on the semiconductor substrate and before the step of etching the semiconductor substrate. Since it has a step of performing the etching process used, the mask layer is formed in the step of forming the mask layer by the step.
Since the finer the mask layer is, the more difficult it is to form a residue on the semiconductor substrate without leaving a residue or the like made of the material of the mask layer. And the residue is left behind, the hem and the residue are almost removed, so that the unetched region of the semiconductor substrate can be accurately adjusted to the pattern of the mask layer. Therefore, the semiconductor substrate can be easily processed into a desired fine pattern with high precision.

Further, after the step of etching the semiconductor substrate and before the step of removing the mask layer from the semiconductor substrate, there is a step of etching the mask layer with oxygen plasma. Generated in the step of subjecting the semiconductor substrate to an etching process using a hydrocarbon-based gas plasma with the mask layer as a mask, by polymerizing a component of the hydrocarbon-based gas and a material of the semiconductor substrate on the mask layer. Even if a layer made of a carbon compound is formed, most of such a layer is removed. Therefore, in the step of removing the mask layer from the semiconductor substrate, the mask layer can be easily removed. .

Further, in the semiconductor substrate processing method according to the second aspect of the present invention, the etching process in the step of forming the second semiconductor layer to the third semiconductor layer uses a hydrocarbon-based gas plasma in a vacuum container. After the step of forming the mask layer on the semiconductor substrate, before the step of forming the third semiconductor layer from the second semiconductor layer, and the step of forming the third semiconductor layer from the second semiconductor layer 7 and 8 except that after the step of removing the mask layer from the semiconductor substrate, there is a step of subjecting the mask layer to an etching treatment using oxygen plasma in a vacuum container.
7 is similar to the case of the conventional semiconductor substrate processing method described above, and therefore, in accordance with the case of the conventional semiconductor substrate processing method described above with reference to FIGS. 7 and 8, the third semiconductor layer is changed from the second semiconductor layer to the second semiconductor layer. If the second semiconductor layer is thinly formed in the step of forming the mask layer by the etching process using the mask layer, the third semiconductor layer is formed as the pattern of the mask layer with high accuracy. You can, meanwhile,
In the step of forming the fourth semiconductor layer from the first semiconductor layer, the fourth semiconductor layer is formed by an etching process using the third semiconductor layer as a mask.
The semiconductor layer can be formed with high precision in the pattern of the mask layer.

However, in the case of the semiconductor substrate processing method according to the second aspect of the present invention, the etching process in the step of forming the second semiconductor layer to the third semiconductor layer is performed by using a hydrocarbon gas plasma in the vacuum container. Since the etching selection ratio between the mask layer and the second semiconductor layer is changed from the second semiconductor layer (semiconductor layer 6) to the third in the conventional semiconductor substrate processing method described above with reference to FIGS. It can be made larger than that in the case where an etching solution is used for the etching treatment for forming the semiconductor layer (semiconductor layer 16) of FIG. Therefore, the semiconductor substrate can be formed into a desired fine pattern.
It can be easily processed with high precision.

Further, after the step of forming the mask layer on the semiconductor substrate and before the step of forming the second semiconductor layer to the third semiconductor layer, the mask layer is etched with oxygen plasma in the vacuum container. Since the process has a step of performing a process, it is possible to form the mask layer in the step of forming the mask layer without a hem and without leaving a residue or the like made of the material of the mask layer on the semiconductor substrate. Since the finer the mask layer is, the more difficult it is, so even if such a hem or a residue is left, such a hem and the residue are almost removed, Therefore, in the step of forming the third semiconductor layer from the second semiconductor layer, the third semiconductor layer is formed so as to correspond to the pattern of the mask layer with high accuracy, and thus the semiconductor substrate is formed. , Phase of fine patterns - the emissions, with high accuracy, can be easily processed.

Further, after the step of forming the third semiconductor layer from the second semiconductor layer and before the step of removing the mask layer from the semiconductor substrate, the mask layer is etched with oxygen plasma in the vacuum container. Since the method includes a step of performing a treatment, in the step of forming the third semiconductor layer from the second semiconductor layer by the step, the component of the hydrocarbon-based gas and the material of the second semiconductor layer are formed on the mask layer. Even if a layer made of a carbon compound produced by polymerization is formed, most of such layer is removed. Therefore, in the step of removing the mask layer from the semiconductor substrate, the mask layer is easily removed. Can be removed.

[0032]

First Embodiment Next, a first embodiment of the semiconductor substrate processing method according to the present invention will be described with reference to FIGS.

1 and 2, parts corresponding to those in FIG. 6 are designated by the same reference numerals.

In the semiconductor substrate processing method according to the present invention shown in FIGS. 1 and 2, the semiconductor substrate is processed by the following sequential steps.

That is, as in the case of the conventional semiconductor substrate processing method described above with reference to FIG. 6, the semiconductor substrate 1 made of only the semiconductor substrate body 2 made of InP, for example, is prepared in advance as the semiconductor substrate to be processed. On the semiconductor substrate 1, a mask layer 11 made of a resist such as an electron beam resist is formed in a predetermined pattern by an exposure process using an electron beam and a subsequent development process (see FIG. 1).
A).

Next, in a step (FIG. 1A) of forming the mask layer 11 by subjecting the mask layer 11 to an etching treatment using oxygen plasma in a vacuum container (not shown), the mask layer 11 is coded. Even if it is formed to have a hem as shown by 17, the mask layer 11 is formed on the semiconductor substrate 1.
Even if a residue (not shown) made of the material of the mask layer 11 is left in the region where the mask is not formed, such a hem and the residue are substantially removed (FIG. 1B).

Then, subsequently in the same vacuum chamber, the semiconductor substrate 1 is masked with, for example, ethane and hydrogen, as in the case of the conventional semiconductor substrate processing method described above with reference to FIG. The mask layer 11 is formed on the semiconductor substrate body 2 by performing an etching process using a hydrocarbon-based gas plasma that is a plasma of a mixed gas of 1: 1 with
The groove 13 is formed so as to form the protrusion 12 having a pattern corresponding to (FIG. 1C).

Next, in the same vacuum chamber, the mask layer 11 is subsequently subjected to an etching process using oxygen plasma to form the groove 13 in the semiconductor substrate body 2. Even if a layer 18 made of a carbon compound produced by the polymerization of the above and the material of the semiconductor substrate body 2 is formed on the mask layer 11, such layer 11 is substantially removed (FIG. 2D).

Next, as in the case of the conventional semiconductor substrate processing method described above with reference to FIG.
The mask layer 11 is removed by dissolution using a liquid composed of methylpyrrolidone (FIG. 2E).

The above is the first embodiment of the semiconductor substrate processing method according to the present invention.

Detailed description of the semiconductor substrate processing method according to the present invention shown in FIGS. 1 and 2 will be omitted. After the step of forming the mask layer 11 on the semiconductor substrate 1, the semiconductor substrate 1 (semiconductor substrate body 2) is processed. Oxygen plasma is applied to the mask layer 11 in the vacuum container before the step of performing the etching treatment and after the step of performing the etching treatment on the semiconductor substrate 1 and before the step of removing the mask layer 11 from the semiconductor substrate 1. 6 is similar to the case of the conventional semiconductor substrate processing method described above with reference to FIG. 6, except that each step of performing the etching process is performed. Therefore, according to the case of the conventional semiconductor substrate processing method described above with reference to FIG. Since plasma of a hydrocarbon-based gas is used in the step (FIG. 1C) of etching the semiconductor substrate 1 (semiconductor substrate body 2), the semiconductor substrate 1 (half The body substrate main body 2) is hardly damaged, or even if it is damaged, only a sufficiently small amount of damage is received, and the etching selectivity between the mask layer and the semiconductor substrate is Since it can be made larger than in the case of using gas plasma, the unetched region (protrusion 12) of the semiconductor substrate is formed as a side etching amount is small, and therefore the semiconductor substrate 1 is damaged. Instead, it can be machined to the desired pattern with high precision.

However, in the case of the semiconductor substrate processing method according to the present invention shown in FIGS. 1 and 2, after the step of forming the mask layer 11 on the semiconductor substrate 1 (FIG. 1A), the semiconductor substrate 1 is processed.
Since there is a step (FIG. 1B) of performing etching processing using oxygen plasma on the mask layer 11 before the step (FIG. 1C) of performing etching processing on the (semiconductor substrate body 2), the step is performed as described above. In the step of forming the mask layer 11 (FIG. 1A) by
The mask layer 11 having no hem 18 and on the semiconductor substrate 1.
In order to form a residue (not shown) made of the above material without leaving, since the finer the mask layer 11 is, the more difficult it is to have such a hem 18,
Even if a residue is left, such a hem 18 and most of the residue are removed, so that the non-etched region (protrusion 12) of the semiconductor substrate is not covered by the mask layer 11.
It is formed as a pattern that conforms to the pattern of
Therefore, the semiconductor substrate 1 can be easily processed into a desired fine pattern with high accuracy.

After the step of etching the semiconductor substrate 1 (FIG. 1C) and before the step of removing the mask layer 11 from the semiconductor substrate 1 (FIG. 2E), the mask layer 1 is removed.
1 has an etching process using oxygen plasma (FIG. 2D). Therefore, as described above, the mask layer 11 is used as a mask on the semiconductor substrate 1 (semiconductor substrate body 2) by the above process. In the step of performing the etching treatment using hydrogen-based gas plasma (FIG. 1C), a layer 18 made of a carbon compound produced by the polymerization of the components of the hydrocarbon-based gas and the material of the semiconductor substrate on the mask layer 11.
If such a layer is formed, most of such a layer 18 is removed. Therefore, in the step of removing the mask layer 11 from the semiconductor substrate 1, the mask layer 11 can be easily removed.

[0044]

Second Embodiment Next, a second embodiment of the semiconductor substrate processing method according to the present invention will be described with reference to FIGS.

3 to 5, parts corresponding to those in FIGS. 7 and 8 are designated by the same reference numerals.

In the semiconductor substrate processing method according to the present invention shown in FIGS. 3 to 5, the semiconductor substrate is processed in the following sequential steps.

That is, as in the case of the conventional semiconductor substrate processing method described above with reference to FIGS. 7 and 8, a semiconductor layer made of, for example, InP and having a thickness of, for example, 500 nm is formed on the semiconductor substrate body 2 made of, for example, InP. 3 and, for example, InG
A semiconductor layer 4 made of aAs and having a thickness of, for example, 5 nm, a semiconductor layer 5 made of InP and having a thickness of, for example, 80 nm, and a semiconductor layer 6 made of, for example, InGaAs and having a thickness of, for example, 3 nm. Assuming that the semiconductor substrate 1 having a structure in which these are laminated in that order is prepared in advance as a semiconductor substrate to be processed, a mask made of a resist such as an electron beam resist is provided on the semiconductor substrate 1. The layer 11 is formed into a predetermined pattern by an exposure process using an electron beam and a subsequent development process (FIG. 3A).

Next, in the step (FIG. 3A) of forming the mask layer 11 by subjecting the mask layer 11 to an etching treatment using oxygen plasma in a vacuum container (not shown), the mask layer 11 is coded. Even if the mask layer 11 is formed to have a hem as shown in FIG. 17, in a region where the mask layer 11 is not formed on the semiconductor substrate 1 (semiconductor layer 6), a residue (not shown) due to the material of the mask layer 11 is shown. Such as hem), such hem 17 and residues are substantially removed (FIG. 4B).

Then, subsequently in the vacuum container, the semiconductor substrate 1 is masked with the mask layer 11 as in the conventional semiconductor substrate processing method described above with reference to FIGS. The semiconductor layer 6 to the mask layer 11 are subjected to an etching treatment using a hydrocarbon-based gas plasma which is a plasma of a mixed gas of 1: 1 and hydrogen.
Forming a semiconductor layer 16 having a pattern corresponding to (FIG. 4C).

Next, in the step of forming the semiconductor layer 6 from the semiconductor layer 16 by subjecting the mask layer 11 to etching treatment using oxygen plasma subsequently in the same vacuum chamber, the components of the hydrocarbon-based gas are Even if a layer 18 made of a carbon compound produced by the polymerization of the above and the material of the semiconductor layer 16 is formed on the mask layer 11, such layer 18 is substantially removed (FIG. 4D).

Next, as in the case of the conventional semiconductor substrate processing method described above with reference to FIGS. 7 and 8, the mask layer 11 is removed from the semiconductor substrate 1 (FIG. 5E).

Next, with respect to the semiconductor substrate 1, FIGS.
As in the case of the conventional semiconductor substrate processing method described above, the semiconductor layer 16 is used as a mask, for example, 3: 1 chlorine and water.
By performing an etching process using an etching solution composed of a solution of
A semiconductor layer 15 having a pattern corresponding to 6 is formed (FIG. 5F).

Next, with respect to the semiconductor substrate 1, FIGS.
As in the case of the conventional semiconductor substrate processing method described above, the semiconductor layer 16 to the semiconductor layer 15 are used as a mask, for example, a sulfuric acid-based solution of sulfuric acid, hydrogen peroxide, and water in a ratio of 1: 1: 20. By performing an etching process using an etching solution, a semiconductor layer 14 having a pattern corresponding to the semiconductor layer 15 is formed from the semiconductor layer 4 (FIG. 5).
G). In this case, the semiconductor layer 16 has the same I
Since it is made of nGaAs and has a smaller thickness than the semiconductor layer 4, it is removed from the semiconductor layer 15.

The above is the second embodiment of the semiconductor substrate processing method according to the present invention.

The semiconductor substrate processing method according to the present invention shown in FIGS. 3 to 5 is not described in detail, but the semiconductor layer 16 is used.
The etching process in the step of forming the semiconductor layer 6 from FIG. 4C (FIG. 4C) is performed using a hydrocarbon-based gas plasma in a vacuum container, and after the step of forming the mask layer 11 on the semiconductor substrate 1, the semiconductor layer Before the step of forming the semiconductor layer 6 from the semiconductor layer 16 and after the step of forming the semiconductor layer 6 from the semiconductor layer 16 and before the step of removing the mask layer 11 from the semiconductor substrate 1 with respect to the mask layer 11 in a vacuum container. , A step of performing an etching process using oxygen plasma (see FIG. 4).
B, and FIG. 5D), respectively.
7 is similar to the case of the conventional semiconductor substrate processing method described above with reference to FIG. 8, and accordingly, the semiconductor layer 6 is replaced with the semiconductor layer 1 according to the case of the conventional semiconductor substrate processing method described above with reference to FIGS.
If the semiconductor layer 16 is thinly formed in the step (FIG. 4C) of forming the mask layer 11 by the etching process using the mask layer 11 as a mask, the semiconductor layer 6 is accurately patterned according to the pattern of the mask layer 11. The semiconductor layers 5 to 4 may be formed as the semiconductor layers 15 to 14
5F to 5G, since the semiconductor layers 5 to 4 are formed by the etching process using the semiconductor layer 6 as a mask, the semiconductor layers 5 to 4 are used as patterns of the mask layer 11. It can be formed as one having high precision.

However, in the case of the semiconductor substrate processing method according to the present invention shown in FIGS. 3 to 7, the etching process in the step of forming the semiconductor layer 16 from the semiconductor layer 16 uses the hydrocarbon-based gas plasma in the vacuum container. Since the etching selection ratio between the mask layer 11 and the semiconductor layer 16 is set to the etching treatment when the semiconductor layer 16 is formed from the semiconductor layer 16 in the conventional semiconductor substrate processing method described above with reference to FIGS. It can be made larger than when an etching solution is used, and therefore, the semiconductor layer 6 can be formed with almost no side etching. Therefore, the semiconductor substrate 1 can be formed into a desired fine pattern.
It can be easily and accurately processed.

After the step of forming the mask layer 11 on the semiconductor substrate 1 (FIG. 3A), the semiconductor layers 16 to 6 are formed.
Before the step of forming (FIG. 4C), in a vacuum container,
Since there is a step (FIG. 4B) of etching the mask layer 11 using oxygen plasma, in the step (FIG. 3A) of forming the mask layer 11 by the step,
Since it is difficult to form the mask layer 11 without the hem 17 and without leaving a residue or the like made of the material of the mask layer on the semiconductor substrate 1, the finer the mask layer 11 is, the more difficult it is. Even if it has such a skirt 17 or leaves a residue, such a hem 17 and the residue are almost removed, so that the step of forming the semiconductor layer 6 from the semiconductor layer 16 ( In FIG. 4C), the semiconductor layer 6 is formed so as to correspond to the pattern of the mask layer 11 with high precision, and thus the semiconductor substrate 1 is formed into the desired fine pattern with high precision. , Can be easily processed.

Further, after the step of forming the semiconductor layer 6 from the semiconductor layer 16 and before the step of removing the mask layer 11 from the semiconductor substrate 1, the mask layer 11 is subjected to an etching treatment using oxygen plasma in a vacuum chamber. 4D), the semiconductor layer 16
In the step of forming the semiconductor layer 6 from the above (FIG. 5E), the hydrocarbon-based gas component and the semiconductor layer 16 are formed on the mask layer 11.
Layer 1 made of a carbon compound produced by polymerization with the above materials
8 is formed, most of such layer 18 is removed, and thus mask layer 11 is applied to semiconductor substrate 1
In the step of removing from above (FIG. 5E), the mask layer 11 can be easily removed.

In the first embodiment of the semiconductor substrate processing method according to the present invention described above with reference to FIGS. 1 and 2, the present invention is applied to the case where the semiconductor substrate 1 having only the semiconductor substrate body 2 is processed. However, the present invention is applied to the case of processing a semiconductor substrate having a structure in which the semiconductor layer is formed as a single layer or a plurality of semiconductor layers are laminated on the semiconductor substrate body 2. By applying it, it is possible to obtain the same effect as that of the first embodiment of the semiconductor substrate processing method according to the present invention described above with reference to FIGS.

In the second embodiment of the semiconductor substrate processing method according to the present invention described above with reference to FIGS. 3 to 5, four semiconductor layers 3, 4, 5 and 6 are laminated on the semiconductor substrate body 2. The case where the present invention is applied to the case where the semiconductor substrate 1 having the formed structure is processed has been described, but the first and second semiconductor layers are each a single layer or a plurality of semiconductors on the semiconductor substrate body. A second embodiment of the semiconductor substrate processing method according to the present invention described above with reference to FIGS. 3 to 5 by applying the present invention when processing a semiconductor substrate having a structure formed by stacking layers. It is also possible to obtain the same effect as the above case.

Furthermore, in each of the embodiments of the semiconductor substrate processing method according to the present invention described above, the case where the mask layer 11 is formed of the electron beam resist has been described. Even when it is formed of various resists other than the electron beam resist including the photoresist, it is possible to obtain the effects of the respective embodiments of the semiconductor substrate processing method according to the present invention described above.
Besides, various modifications and changes may be made without departing from the spirit of the present invention.

[Brief description of drawings]

FIG. 1 is a schematic sectional view in a sequential process showing a first embodiment of a semiconductor substrate processing method according to the present invention.

FIG. 2 is a schematic cross-sectional view showing a first embodiment of a semiconductor substrate processing method according to the present invention in a sequential process subsequent to the sequential process in FIG.

FIG. 3 is a schematic sectional view in the first step showing the second embodiment of the semiconductor substrate processing method according to the present invention.

FIG. 4 is a schematic cross-sectional view showing a second embodiment of the semiconductor substrate processing method according to the present invention in successive steps following the step of FIG.

FIG. 5 is a schematic cross-sectional view showing a second embodiment of the semiconductor substrate processing method according to the present invention in a sequential process subsequent to the sequential process in FIG.

FIG. 6 is a schematic cross-sectional view in a sequential process showing a conventional semiconductor substrate processing method.

FIG. 7 is a schematic cross-sectional view in a sequential process showing another conventional semiconductor substrate processing method.

FIG. 8 is a schematic cross-sectional view showing another conventional semiconductor substrate processing method in a sequential process subsequent to the sequential process in FIG. 7.

[Explanation of symbols]

 1 Semiconductor Substrate 2 Semiconductor Substrate Body 3, 4, 5, 6 Semiconductor Layer 11 Mask Layer 12 Projection 13 Grooves 14, 15, 16 Semiconductor Layer 17 Bottom 18 Layer

Claims (2)

[Claims] 1. A step of forming a mask layer made of a resist on a semiconductor substrate prepared in advance, which has a structure in which a semiconductor layer is formed or not formed on a semiconductor substrate body, and after the step, A step of subjecting the mask layer to an etching treatment using oxygen plasma in a vacuum container, and, after that step, a hydrocarbon-based mask using the mask layer as a mask for the semiconductor substrate. A step of performing an etching process using gas plasma, a step of performing an etching process using oxygen plasma on the mask layer after the step, and a step of performing an etching process using oxygen plasma on the semiconductor substrate after the step. And a step of removing the mask layer, the method for processing a semiconductor substrate. 2. A resist prepared on a semiconductor substrate prepared in advance, which has a structure in which first and second semiconductor layers having different compositions are laminated in this order on a semiconductor substrate body. And a step of performing an etching process using oxygen plasma on the mask layer in a vacuum container after the step of forming a mask layer consisting of A pattern corresponding to the mask layer is formed from the second semiconductor layer by subjecting the second semiconductor layer of the substrate to an etching process using a hydrocarbon-based gas plasma using the mask layer as a mask. A step of forming a third semiconductor layer having a silicon layer, and a step of performing an etching process using oxygen plasma on the mask layer after the step of forming the third semiconductor layer. After that, a step of removing the mask layer from the semiconductor substrate, and after the step, an etching process using an etching solution with the third semiconductor layer as a mask is performed on the first semiconductor layer. From the first semiconductor layer,
And a step of forming a fourth semiconductor layer having a pattern corresponding to the third semiconductor layer.