TW202425177A - Film forming device capable of avoiding the need to define a horizontal through hole in the base so that the preparation is simpler and easier to implement - Google Patents

Abstract

The present invention discloses a film forming device, which comprises a reaction chamber, and a base, a support column and a process kit arranged inside the reaction chamber. The reaction chamber provides a closed environment for wafer processing. The support column is arranged below the base to support the base. The process kit is arranged around the base to cooperate with the base or the side chamber wall of the reaction chamber to form a purging gas channel. The upper surface of the base has a boss, through which the wafer is carried, and the edge area of the base is provided with a channel running through the upper surface and lower surface of the base. The purging gas is introduced into the edge position of the wafer to purge the edge and back of the wafer, preventing the reaction gas during the wafer processing from being deposited on the edge and back of the wafer. The present invention avoids the need to define a horizontal through hole in the base, making the preparation simpler and easier to implement, and reducing the manufacturing cost, thereby providing good application prospects.

Description

Film forming device

The present invention belongs to the field of semiconductor equipment, and specifically relates to a film forming device.

In the semiconductor production process, reactive gases are usually used to process wafers to generate material layers that constitute integrated circuits. Common methods include chemical vapor deposition, physical vapor deposition, epitaxial growth, etc. The pedestal used to support the wafer in the processing chamber usually has a heating function. While the reactive gas is introduced into the reaction chamber to process the wafer, the wafer is also heated through the pedestal to generate a thin film on the surface of the wafer to form a material layer.

During the wafer processing, the reactive gas tends to deposit on the edge and back of the wafer. The film at the edge of the wafer will be thicker, and as the reaction proceeds, the film at the edge of the wafer becomes thicker, which may cause cracking and falling off as well as particle problems, thus causing the wafer to be damaged and substandard, affecting the performance of the device. In order to protect the edge of the wafer from being contacted by the reactive gas, purge gas is usually introduced at the edge of the wafer to prevent the reactive gas in the processing chamber from diffusing to the vicinity of the edge of the wafer.

The existing design opens a horizontal through hole in the base, and the purge gas enters the horizontal through hole from the bottom of the base, and introduces the purge gas to the edge of the wafer through the horizontal through hole; however, for a base made of ceramic materials such as aluminum nitride (AlN) or aluminum oxide (AlOx), it is very difficult to open a horizontal through hole inside it. Currently, only very few companies have the manufacturing capability, and the manufacturing cost is very high. In addition, in addition to a set of conventional gas supply devices to supply purge gas to the processing chamber, the existing design also requires the installation of an additional gas supply device to supply purge gas to the horizontal through hole opened in the base.

The purpose of the present invention is to provide a film forming device, which introduces a purge gas to the edge of a wafer by opening a channel penetrating the upper and lower surfaces of the susceptor in the edge area of the susceptor, and purges the edge and back of the wafer to prevent the reaction gas in the processing chamber from being deposited on the edge and back of the wafer, thereby avoiding the need to open a horizontal through hole in the susceptor. Another purpose of the present invention is to use the same purge gas introduced into the reaction chamber to purge the edge of the wafer and the channel between the process kit and the side wall of the reaction chamber, thereby simplifying the purge gas supply system.

The film forming device provided by the present invention comprises a reaction chamber, wherein a base, a support column for supporting the lower surface of the base and a process kit surrounding the base are arranged in the reaction chamber, and the upper surface of the base is used to carry a wafer; A first channel penetrating the upper and lower surfaces of the base is opened in the edge area of the base, and a first gas flows through the first channel to sweep the edge of the wafer; A second channel is formed between the process kit and the side cavity wall of the reaction chamber, and a second gas sweeps the second channel.

Optionally, the upper surface of the base includes a boss for supporting the wafer; The diameter of the boss is smaller than the diameter of the wafer; The first gas is also used to blow the back side of the wafer.

Optionally, the first gas and the second gas are derived from the same purge gas introduced into the reaction chamber.

Optionally, the channel width of at least one of the first channel and the second channel is changed to adjust the flow rate of the first gas and the second gas.

Optionally, the process kit includes an annular side wall and an extension portion located at the upper end of the side wall; The annular side wall is located between the side surface of the base and the side cavity wall; The extension portion is located above the base.

Optionally, the extension portion is located above the edge area to limit the flow path of the first gas flowing out of the first channel.

Optionally, the lower end of the annular side wall is lower than the lower surface of the base.

Optionally, the process kit can be detachably installed in the reaction chamber; The film forming device is equipped with multiple process kits, each of which can be used in conjunction with a base.

Optionally, the thickness of the extension portion of some process kits is different, which is used to change the size of the gap between the extension portion and the top surface of the edge area of the base.

Optionally, the thickness of the annular side walls of some process kits is different, which is used to change the channel width of the second channel.

Optionally, the purge gas is introduced from the bottom cavity wall of the reaction chamber, or from the bottom side wall of the supporting column.

Optionally, the first gas and the second gas are respectively derived from purge gases introduced into the reaction chamber through different paths.

Optionally, the flow rates of the purge gases introduced into the reaction chamber from different paths are independently controllable.

Optionally, the purge gas corresponding to the second gas path is introduced from the bottom cavity wall of the reaction chamber.

Optionally, the first gas is introduced through at least one gas pipeline, and the blowing gas in the gas pipeline is transmitted to the first channel after passing through a gas homogenizing component.

Optionally, the air homogenizing component is a hollow annular component.

Optionally, the first channel includes at least one of an arc-shaped channel and a hole-shaped channel.

Optionally, the first channel is a vertically arranged through channel.

Optionally, a heater is provided in the base.

Optionally, the material of the base is one or more of ceramic, metal and graphite.

Compared with the prior art, the advantages or beneficial effects of the present invention are:

The film forming device provided by the present invention avoids opening a horizontal through hole in the base by opening a first channel penetrating the upper and lower surfaces of the base in the edge area of the base, thereby reducing the difficulty of manufacturing the base. The purge gas is introduced to the edge position of the wafer to purge the edge and back of the wafer, thereby preventing the reaction gas in the processing chamber from diffusing to the edge and back of the wafer and depositing.

In addition, in the film forming device provided by the present invention, the first gas for blowing the edge and back of the wafer and the second gas for blowing between the process kit and the side wall of the reaction chamber can use the same blowing gas introduced into the reaction chamber, thereby simplifying the gas supply system for supplying the blowing gas to the reaction chamber and saving manufacturing costs.

In the film forming device provided by the present invention, the first gas for blowing the edge and back of the wafer and the second gas for blowing between the process kit and the side wall of the reaction chamber can also use blowing gases introduced into the reaction chamber from different paths. The flow rates of the blowing gases introduced into the reaction chamber from different paths are independently controllable, thereby basically realizing the independent regulation of the flow rates of the first gas and the second gas to meet special process requirements.

In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be described clearly and completely in combination with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making progressive labor are within the scope of protection of the present invention.

It should be noted that, in this article, the terms "include", "comprising", "having" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or terminal device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or terminal device. In the absence of more restrictions, the elements defined by the phrase "include..." or "comprising..." do not exclude the existence of other elements in the process, method, article or terminal device including the elements.

It should be noted that the drawings are all in very simplified form and use non-precise ratios, and are only used to conveniently and clearly assist in explaining an embodiment of the present invention.

The film forming device provided by the present invention is used to process wafers, generate thin films on the wafer surfaces, and form material layers during the semiconductor production and preparation process. The film forming device mainly includes a reaction chamber, and a base, a supporting column and a process kit arranged inside the reaction chamber; wherein the reaction chamber is used to provide a closed place for wafer processing; the supporting column is arranged below the base to support the base; the process kit is arranged around the base to cooperate with the base or the side cavity wall of the reaction chamber to form a channel for blowing gas; the upper surface of the base has a boss, and the wafer is supported by the boss, and the edge area of the base is opened with a channel penetrating the upper and lower surfaces of the base, so that the blowing gas is introduced into the edge position of the wafer, and the edge and back of the wafer are blown to prevent the reaction gas in the wafer processing process from being deposited on the edge and back of the wafer, thereby avoiding the need to open a horizontal through hole in the base.

Embodiment 1

FIG1 is a schematic diagram of the structure of the film forming device in the first embodiment of the present invention, and FIG2 and FIG3 are partial schematic diagrams of the film forming device. Referring to FIG1 to FIG3 , the film forming device 100 includes a reaction chamber 110 , a base 120 , a support column 130 and a process kit 140 .

In the present invention, the base 120 is made of one or more materials selected from ceramic, metal and graphite; and a heater (not shown in the figure) is provided inside the base 120 for heating the wafer during the wafer processing process to promote the formation of a thin film on the wafer surface.

The reaction chamber 110 is a closed chamber. During the wafer processing process, the reaction gas enters the reaction chamber from the upper area of the reaction chamber 110 to process the wafer 150 in the reaction chamber, thereby generating a thin film and forming a material layer on the surface of the wafer 150; the purge gas enters the reaction chamber from the lower area of the reaction chamber 110 to purge the surface of the component to prevent the reaction gas from diffusing to the surface of the component for deposition, etc. The purge gas does not participate in the reaction processing of the wafer. Common purge gas is one of inert gas, hydrogen and nitrogen, or a mixture thereof.

The support column 130 is disposed inside the reaction chamber 110 ; the support column 130 is located below the base 120 and is used to support the base.

The base 120 is located at the top of the support column 130. Optionally, a boss 120a is provided on the upper surface of the base 120, the boss 120a is located in the middle of the base 120, and the upper surface of the boss 120a is higher than the upper surface of the edge area 120b of the base, and the edge area 120b of the base surrounds the boss 120a. The boss 120a is used to support the wafer 150, and the diameter of the boss 120a is smaller than the diameter of the wafer 150. Therefore, for the wafer located on the boss, its edge and back are both located in the upper area of the edge area 120b; during the processing of the wafer, the reaction gas enters from the upper area of the reaction chamber 110, diffuses downward to the upper surface of the wafer, and forms a thin film on the upper surface of the wafer, and at the same time diffuses to the edge 150a of the wafer and the back 150b of the wafer (referring to the portion of the lower surface of the wafer that is not in contact with the boss), so that the edge 150a and the back 150b of the wafer are exposed to the reaction gas.

In order to prevent the reaction gas from diffusing to the edge and back of the wafer, the present invention opens a plurality of first channels 160 in the edge area 120b; each first channel 160 penetrates the upper surface and the lower surface of the edge area 120b. The purge gas enters the first channel 160 from the lower surface of the edge area 120b to form a first gas A, and the first gas A flowing out from the upper surface of the edge area 120b purges the wafer portion above the edge area 120b, thereby preventing the reaction gas from diffusing to the edge 150a and back 150b of the wafer. The present invention opens the first channel 160 in the edge area 120b, thereby avoiding the need to open a horizontal through hole in the base, and reducing the difficulty of manufacturing the base 120.

In one embodiment of the present invention, the first channel 160 is an arc-shaped channel, as shown in FIG4 , the edge region 120b is provided with a plurality of arc-shaped first channels 160; in another embodiment of the present invention, the first channel 160 is a hole-shaped channel, as shown in FIG5 , the edge region 120b is provided with a plurality of hole-shaped first channels 160. It should be noted that in other embodiments, the first channel 160 may also be configured as a through channel of other shapes as required, and the present invention is not limited thereto.

From the upper surface of the edge region 120b to the lower surface of the edge region 120b, the first channel 160 is vertically arranged and penetrates the edge region 120b. In other embodiments, the first channel 160 can also be configured as an inclined or other structural through-channel as needed, and the present invention is not limited here.

The process kit 140 is disposed around the base 120 and is used to cooperate with the base 120 or the side chamber wall 110b of the reaction chamber to form a channel for the purge gas. The process kit 140 further includes a side wall 140a and an extension part 140b.

The side wall 140a is annular and is located between the base 120 and the side cavity wall 110b of the reaction chamber, as shown in FIG3 ; the inner side of the side wall 140a is arranged closely to the base 120, and a gap is formed between the outer side of the side wall 140a and the side cavity wall 110b of the reaction chamber, and the gap is used as the second channel 170. The blowing gas passes through the second channel 170 to form a second gas path B, and the second gas path B blows the side wall 140a and the side cavity wall 110b of the reaction chamber to prevent the reaction gas from diffusing to the surface of the side wall 140a and the side cavity wall 110b and the bottom of the base 120. In some embodiments, the lower end of the side wall 140a is lower than the lower surface of the base 120, so as to facilitate the introduction of the blowing gas into the first channel 160 and the diversion of the blowing gas.

An extension portion 140b is provided at the upper end of the side wall 140a. The extension portion 140b is annular. The outer edge of the extension portion 140b is connected to the upper end of the side wall 140a, and the extension portion 140b is located above the base 120. Specifically, the extension portion 140b is located above the edge area 120b, and is used to limit the flow path of the first gas A flowing out of the first channel 160. Referring to FIG. 2 and FIG. 3, a gap is formed between the lower surface of the extension portion 140b and the top surface of the edge area 120b, and is connected to the gap formed between the back surface 150b of the wafer and the top surface of the edge area 120b, forming a first gap 180, and the first gap 180 is connected to the first channel 160. A second gap 190 is formed between the side wall of the extension portion 140b and the edge of the wafer, and the second gap 190 is connected to the first gap 180; the first gas A flowing out of the first channel 160 will enter the first gap 180 to blow the back side 150b of the wafer, and will continue to flow to the second gap 190 to blow the edge 150a of the wafer.

The process kit 140 is detachably mounted in the film forming apparatus 100. In one embodiment of the present invention, the film forming apparatus 100 has a plurality of process kits 140, each of which can be used in conjunction with the base 120. The thickness of the extension portion 140b of some process kits is different. By using process kits with different thicknesses of the extension portion, the size of the first gap 180 can be changed, thereby changing the flow rate of the first gas A, and controlling the blowing force of the first gas A on the back side 150b and the edge 150a of the wafer. The annular side wall 140a of some process kits has different thicknesses. By adopting process kits with annular side walls 140a of different thicknesses, the size of the second channel 170 can be changed, thereby changing the flow rate of the second gas B and controlling the blowing force of the second gas B on the side wall 140a and the side cavity wall 110b of the reaction chamber.

In the first embodiment of the present invention, the first gas A and the second gas B are derived from the same purge gas C introduced into the reaction chamber. In one embodiment of the present invention, the purge gas C can be introduced from the bottom wall 110a of the reaction chamber 110; in another embodiment of the present invention, the purge gas can be introduced from the bottom side wall 130a of the support column 130. The purge gas C flows from the bottom of the reaction chamber 110 to the upper area of the reaction chamber, so as to prevent the reaction gas from diffusing to the bottom of the reaction chamber 110; the purge gas C blows upward the lower surface of the base 120 and the process kit 140, and part of the purge gas C enters the first channel 160 to form a first gas A to blow the back side 150b and the edge 150a of the wafer; part of the purge gas C enters the second channel 170 to form a second gas B to blow the side wall 140a and the side cavity wall 110b of the reaction chamber.

Embodiment 2

Fig. 6 is a side view of the structure of the film forming device in the second embodiment of the present invention. In the second embodiment of the present invention, the gas supply system 200 includes a reaction chamber 210, a base 220, a support column 230 and a process kit 240.

For the above-mentioned first embodiment, the first gas A and the second gas B are derived from the same purge gas C introduced into the reaction chamber; therefore, the gas supply system 200 can be designed with only one gas supply system to supply the purge gas C into the reaction chamber 110. Although the first embodiment can simplify the device structure, the first gas A and the second gas B are derived from the same purge gas, and it is difficult to achieve the individual control of the flow rates of the first gas A and the second gas B. In particular, for the wafer processing process requiring the flow rate of the first gas A to be different from the flow rate of the second gas B, the film forming device provided by the first embodiment cannot meet the process requirements.

Different from the above-mentioned embodiment 1, in the embodiment 2 of the present invention, the first gas A' and the second gas B' are respectively derived from the purge gas introduced into the reaction chamber through different paths. As shown in FIG6 , in the embodiment 2 of the present invention, the purge gas D' used to form the first gas A' and the purge gas C' used to form the second gas B' are relatively independent and are supplied to the reaction chamber 210 by two gas supply systems. Therefore, the flow rates of the first gas A' and the second gas B' can be basically controlled separately to meet the special process requirements.

In one implementation of the present embodiment, the purge gas C' is introduced from the bottom cavity wall of the reaction chamber, enters the second channel through the reaction chamber 210 to form a second gas path B', and the second gas path B' purges the side wall 240a of the process kit and the side cavity wall 210b of the reaction chamber to prevent the reaction gas from diffusing to the surface of the side wall 240a and the side cavity wall 210b and the bottom of the base 220.

In the second embodiment of the present invention, the gas supply system 200 further includes an air homogenizing component 260, which is a hollow annular component. The air homogenizing component 260 is located in the reaction chamber 210 and below the base 220. The air homogenizing component 260 has a plurality of air outlets, each of which corresponds to the position of the first channel. The blowing gas supplied by the air supply system enters the air homogenizing component 260 through a plurality of gas inlet pipelines (not shown in the figure), and is evenly mixed in the air homogenizing component 260, so that the flow rate of the blowing gas ejected from each air outlet of the air homogenizing component 260 is consistent. The blowing gas ejected from each air outlet enters the first channel to form the first path of gas A'. The first gas A' flowing out of the first channel will enter the first gap to clean the back side of the wafer, and will continue to flow to the second gap to clean the edge of the wafer.

Compared with the above-mentioned embodiment 1, the first gas A' and the second gas B' come from the purge gas introduced into the reaction chamber through different paths, and the flow rates of the purge gas introduced into the reaction chamber through different paths are independently controllable, thereby basically realizing the independent regulation of the flow rates of the first gas and the second gas to meet special process requirements.

The film forming device provided by the present invention avoids opening a horizontal through hole in the base by opening a first channel penetrating the upper and lower surfaces of the base in the edge area of the base, and introduces the blowing gas to the edge position of the wafer to blow the edge and back of the wafer to prevent the reaction gas in the processing chamber from diffusing to the edge of the wafer and depositing on the back.

Although the content of the present invention has been described in detail through the above preferred embodiments, it should be recognized that the above description should not be considered as a limitation of the present invention. After reading the above content, various modifications and substitutions of the present invention will be obvious to those skilled in the art. Therefore, the protection scope of the present invention should be limited by the scope of the patent application of the attached claims.

100: film forming device 110: reaction chamber 110b: side chamber wall 120: base 120a: boss 120b: edge area 130: support column 130a: bottom side wall 140: process kit 140a: side wall 140b: extension part 150: wafer 150a: edge 150b: back side 160: first channel 170: second channel 180: first gap 190: second gap A, A’: first gas B, B’: second gas C, C’: purge gas D’: purge gas 200: gas supply system 210: reaction chamber 210b: side cavity wall 220: base 230: support column 240: process kit 240a: side wall 260: uniform gas component

Figure 1 is a structural side view of the film forming device described in the first embodiment of the present invention; Figures 2 and 3 are partial schematic diagrams of the film forming device; Figures 4 and 5 are top views of the base described in the first embodiment; Figure 6 is a structural side view of the film forming device described in the second embodiment of the present invention.

100: Film forming device

110: Reaction chamber

120: Base

130: Support column

140: Process Kit

150: Wafer

A: First gas

B: Second gas

C: Blowing gas

Claims (20)

A film forming device comprises: A reaction chamber, wherein a susceptor, a support column for supporting the lower surface of the susceptor and a process kit surrounding the susceptor are arranged in the reaction chamber, and the upper surface of the susceptor is used to carry a wafer, wherein a first channel penetrating the upper and lower surfaces of the susceptor is opened at the edge area of the susceptor, and a first gas flows through the first channel to sweep the edge of the wafer; a second channel is formed between the process kit and the side wall of the reaction chamber, and a second gas sweeps the second channel. The film forming device as described in claim 1, wherein the upper surface of the base includes a boss for supporting the wafer; the diameter of the boss is smaller than the diameter of the wafer; and the first gas is also used to blow the back side of the wafer. The film forming device as described in claim 1 or 2, wherein the first gas and the second gas are derived from the same purge gas introduced into the reaction chamber. The film forming device as described in claim 3, wherein the channel width of at least one of the first channel and the second channel is changed to adjust the flow rate of the first gas and the second gas. The film forming device as described in claim 4, wherein the process kit includes an annular side wall and an extension portion located at the upper end of the side wall; the annular side wall is located between the side surface of the base and the side chamber wall; the extension portion is located above the base. The film forming device as described in claim 5, wherein the extension portion is located above the edge region and is used to limit the flow path of the first gas flowing out of the first channel. A film forming device as described in claim 6, wherein the lower end of the annular side wall is lower than the lower surface of the base. The film forming device as described in claim 7, wherein the process kit is detachably mounted in the reaction chamber; the film forming device is equipped with a plurality of the process kits, each of which can be used in conjunction with a base. The film forming device as described in claim 8, wherein the thickness of the extension portion of some of the process kits is different, which is used to change the size of the gap between the extension portion and the top surface of the edge area of the base. The film forming device as described in claim 9, wherein the thickness of the annular sidewall of some of the process kits is different, which is used to change the channel width of the second channel. The film forming device as described in claim 3, wherein the purge gas is introduced from the bottom wall of the reaction chamber, or from the bottom side wall of the support column. The film forming device as described in claim 1 or 2, wherein the first gas and the second gas are respectively derived from purge gases introduced into the reaction chamber from different paths. The film forming device as described in claim 12, wherein the flow rate of the purge gas introduced into the reaction chamber through different paths is independently controllable. The film forming device as described in claim 13, wherein the purge gas corresponding to the second gas path is introduced from the bottom wall of the reaction chamber. The film forming device as described in claim 13, wherein the first gas is introduced through at least one gas pipeline, and the blowing gas in the gas pipeline is transmitted to the first channel after passing through the gas homogenizing component. The film forming device as described in claim 15, wherein the uniform air component is a hollow annular component. The film forming device as described in claim 1, wherein the first channel includes at least one of an arc-shaped channel and a hole-shaped channel. The film forming device as described in claim 1, wherein the first channel is a vertically arranged through channel. The film forming device as described in claim 1, wherein a heater is provided in the base. The film forming device as described in claim 1, wherein the material of the base is one or more of ceramic, metal and graphite.