JPH087626Y2 - Etching equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to an etching apparatus for dry etching a sample, and more particularly to a means for improving its etching characteristics.

[Conventional technology]

FIG. 2 is a schematic diagram showing an example of a conventional etching apparatus.

This device is a so-called batch type ion beam etching device, and a rotating disk 19 is rotated in the vacuum container 16 by a driving device 20 at a high speed as indicated by an arrow A, for example.
Are provided, and a plurality of samples 18 are attached to the peripheral portion of the sample 18 at predetermined intervals. Then, the sample 18 at a predetermined position is irradiated with the ion beam 14 for etching extracted from the ion source 2 for etching attached to the vacuum container 16, so that each sample 18 is sequentially etched.

The etching ion source 2 is an ECR type ion source in this example, and supplies a gas (for example, a reactive gas such as CF ₄ or CCl ₄ ) 12 into the plasma generation container 4 from a gas source (not shown) and also microwaves. A plasma is generated by supplying microwave power from an oscillator 10, and an extraction electrode system 8 is used to extract an ion beam 14 containing, for example, reactive ions from the plasma. 6 is a magnetic field coil for plasma confinement.

The sample 18 is, for example, as shown in FIG.
The surface of a substrate 181 made of Al is covered with a material to be etched 182 made of Al, Ti, or the like, and further covered with a resist (photoresist) 183 having a desired pattern. When the ion beam 14 is irradiated, the material 182 to be etched is etched according to the pattern of the resist 183.

[Problems to be solved by the invention]

When the sample 18 is etched as described above, if the resisting resistance of the resist 183 is poor, the selectivity of the material to be etched 182 with respect to the resist is reduced, and therefore the thickness of the resist 183 must be increased. This causes a problem that accurate patterning of the resist 183 becomes difficult.

Further, a natural oxide film is easily formed on the exposed surface of the material to be etched 182.
The etching rate of the sample 18 decreases more and more, and the etching selectivity of the material to be etched 182 becomes unstable due to the variation in the formation of the oxide film. There is a problem that the yield decreases and the yield also deteriorates.

Therefore, the main object of the present invention is to provide an etching apparatus capable of improving the etching resistance of the resist in the sample and removing the oxide film on the surface of the material to be etched.

[Means for solving problems]

The etching apparatus of the present invention is equipped with a vacuum container, a rotary disk that is housed in the vacuum container and has a plurality of samples mounted on the peripheral edge thereof, a drive device that rotates the rotary disk, and the rotary disk. And a pretreatment ion source for pretreating the sample at a predetermined position on the rotating disk by irradiating the sample with a pretreatment ion beam, and the predetermined position on the rotating disk attached to the vacuum container. And an ion source for etching that etches the sample by irradiating the sample at a position different from that with the ion beam for etching.

[Action]

According to the above configuration, the sample at the predetermined position on the rotating disk is irradiated with the pretreatment ion beam from the pretreatment ion source to improve the etching resistance property of the resist in the sample and to improve the surface of the material to be etched. In parallel with performing pretreatment such as oxide film removal, the sample at a position different from the predetermined position on the rotating disk is etched by irradiating an ion beam for etching from an ion source for etching. You can

〔Example〕

FIG. 1 is a schematic view showing an etching apparatus according to an embodiment of the present invention. The same or corresponding portions as those of the conventional example shown in FIG. 2 are designated by the same reference numerals, and the difference from the same is mainly described below.

In this embodiment, the vacuum container 16 having the etching ion source 2 for dry etching the sample 18 is attached.
Further, another pretreatment ion source 22 is further attached, and the pretreatment ion beam 34 extracted therefrom is attached to the rotating disk 19
The sample 18 above is irradiated. In this case, the rotating disk 19 is a region where the sample 18 is irradiated with the ion beam 14 for etching by the etching ion source 2 from the pretreatment region where the ion beam 34 from the pretreatment ion source 22 is irradiated (that is, an etching region). ) Also works as a moving means.

The pretreatment ion source 22 is a bucket type ion source in this example, and the gas 32 is introduced into the plasma generation container 24,
An arc discharge is caused between the plasma generating container 24 also serving as an anode and the filament 30 to generate plasma in the plasma generating container 24, and the ion beam 34 for pretreatment is extracted from this plasma by the action of the electric field by the extraction electrode system 28. Is configured. 26 is a magnet for generating a plasma confining magnetic field.

According to the above configuration, while rotating the rotary disk 19 and sequentially irradiating the sample 18 thereon with the ion beam 14 from the ion source 2 for etching, the sample 18 on the rotary disk 19 is irradiated with the ion beam 14. The ion beam 34 from the pretreatment ion source 22 can be irradiated continuously or intermittently.

In that case, by extracting the ion beam 34 containing, for example, H ions from the pretreatment ion source 22 and irradiating the sample 18 with the ion beam 34, the resist 183 is hardened and its heat resistant temperature rises. The etching characteristics can be improved.

Alternatively, the oxide film on the surface of the material to be etched 182 can be removed by reduction or the like by extracting the ion beam 34 containing, for example, CF ₃ ions from the pretreatment ion source 22 and irradiating the sample 18 with this. By the way, this effect is remarkable when the material to be etched 182 is an active material such as Al or Ti, and is also great when the residual gas pressure in the vacuum container 16 is somewhat high.

Further, by using a mixed ion beam of the above-mentioned ion species as the ion beam 34, both effects described above can be obtained together. Of course, the ion species extracted as the ion beam 34 may be appropriately switched to the one described above.

The sample 18 that has been subjected to the pretreatment as described above by irradiation with the ion beam 34 has an improved etching resistance property of the resist 183 and an etching rate of the material 182 to be etched. growing. Further, since the oxide film that causes the variation of the etching rate is removed, the etching rate of the material to be etched 182 becomes stable, which improves the reproducibility of the etching of the sample 18 and thus improves the yield.

Moreover, while rotating the rotating disk 19, the same sample 18 mounted on it is subjected to pretreatment by irradiation of the ion beam 34 from the pretreatment ion source 22 and irradiation of the ion beam 14 from the etching ion source 2. Since etching and etching can be performed continuously, the resist on the sample surface
Layers having an improved heat resistant temperature can be successively formed on the surface of 183. As a result, unlike the case where the pretreatment is performed only once on the same sample, there is no fear that the layer having an improved heat resistant temperature will be removed by etching due to the irradiation of the ion beam 14, and thus the resist 183 will be resistant to etching. Etching can be performed while maintaining the characteristics in good condition, and the etching characteristics are further improved.

[Effect of device]

As described above, according to the present invention, the sample subjected to the pretreatment such as the improvement of the etching resistance of the resist by the pretreatment ion source and the removal of the oxide film on the material to be etched is etched by the etching ion source. Therefore, the etching selectivity of the material to be etched in the sample is increased, the etching rate of the material to be etched is stabilized, and the etching characteristics are improved.

Moreover, while rotating the rotating disk, pretreatment by the pretreatment ion source and etching by the etching ion source can be continuously performed on the same sample mounted thereon, so that the surface of the resist is Layers with improved heat resistance can be produced one after another. As a result, unlike the case where the pretreatment is performed only once for the same sample, there is no risk of the layer having an improved heat-resistant temperature being scraped away by etching, so that the etching resistance of the resist is maintained in a good state. It is possible to carry out etching while improving the etching characteristics.

[Brief description of drawings]

FIG. 1 is a schematic view showing an etching apparatus according to an embodiment of the present invention. FIG. 2 is a schematic diagram showing an example of a conventional etching apparatus. FIG. 3 is a sectional view partially showing an example of the sample. 2 …… Etching ion source, 22 …… Pretreatment ion source, 14,34 …… Ion beam, 16,36,38 …… Vacuum container, 1
8 …… Sample, 182 …… Material to be etched, 183 …… Resist, 19 …… Rotating disk, 46 …… High frequency power supply, 50 …… Plasma.

Claims (1)

[Scope of utility model registration request] 1. A vacuum container, and a rotary disk which is housed in the vacuum container and has a plurality of samples mounted on its peripheral edge.
A drive device for rotating the rotating disk, and a pretreatment ion source for pretreating the sample by irradiating the sample at a predetermined position on the rotating disk with a pretreatment ion beam attached to the vacuum container. An etching ion source that is attached to the vacuum container and irradiates a sample at a position different from the predetermined position on the rotating disk with an ion beam for etching to etch the sample. apparatus.