阅读说明：本技术 多晶硅薄膜沉积系统及方法 (Polycrystalline silicon film deposition system and method ) 是由 郭帅 王秉国 吴功莲 蒲浩 潘国卫 于 2019-08-27 设计创作，主要内容包括：本发明提供一种多晶硅薄膜沉积系统及方法,包括：晶圆装载腔室；工艺腔室,与所述装载腔室相连通；含氧气体供给装置,包括含氧气体供给管路,含氧气体供给管路的一端延伸至晶圆装载腔室的内部,用于至少在多晶硅薄膜沉积之后将晶圆自工艺腔室向晶圆装载腔室内传送的过程中向晶圆装载腔室内提供含氧气体；保护气体供给装置,包括保护气体供给管路,保护气体供给管路的一端延伸至晶圆装载腔室的内部,用于至少在含氧气体供给装置未向晶圆装载腔室内提供所述含氧气体时向晶圆装载腔室内提供保护气体。本发明可以对晶圆表面沉积的多晶硅薄膜的表面进行氧化,避免对后续光刻制程工艺的不良影响,确保后续光刻制程工艺的关键尺寸具有较好的均匀性。(The invention provides a polysilicon film deposition system and a method, comprising the following steps: a wafer loading chamber; a process chamber in communication with the loading chamber; the oxygen-containing gas supply device comprises an oxygen-containing gas supply pipeline, one end of the oxygen-containing gas supply pipeline extends to the interior of the wafer loading chamber and is used for supplying oxygen-containing gas into the wafer loading chamber at least in the process of transferring the wafers from the process chamber into the wafer loading chamber after the polycrystalline silicon thin film is deposited; and the protective gas supply device comprises a protective gas supply pipeline, one end of the protective gas supply pipeline extends to the interior of the wafer loading chamber and is used for supplying protective gas into the wafer loading chamber at least when the oxygen-containing gas supply device does not supply the oxygen-containing gas into the wafer loading chamber. The method can oxidize the surface of the polycrystalline silicon film deposited on the surface of the wafer, avoid the adverse effect on the subsequent photoetching process, and ensure that the key dimension of the subsequent photoetching process has better uniformity.)

1. A polysilicon thin film deposition system, comprising:

the wafer loading chamber is used for loading a wafer which needs to be subjected to polycrystalline silicon film deposition;

the process chamber is communicated with the wafer loading chamber and is used for depositing a polycrystalline silicon film on the surface of the loaded wafer;

the oxygen-containing gas supply device comprises an oxygen-containing gas supply pipeline, one end of the oxygen-containing gas supply pipeline extends to the interior of the wafer loading chamber and is used for supplying oxygen-containing gas into the wafer loading chamber at least in the process of transferring the wafers from the process chamber into the wafer loading chamber after the deposition of the polycrystalline silicon thin film; and

and the protective gas supply device comprises a protective gas supply pipeline, one end of the protective gas supply pipeline extends to the interior of the wafer loading chamber and is used for supplying protective gas into the wafer loading chamber at least when the oxygen-containing gas supply device does not supply the oxygen-containing gas into the wafer loading chamber.

2. The polysilicon thin film deposition system of claim 1, further comprising a baffle plate positioned between the wafer loading chamber and the process chamber for isolating the wafer loading chamber from the process chamber before the transfer of the wafer to the process chamber and after the transfer of the wafer to the wafer loading chamber.

3. The polysilicon thin film deposition system of claim 1, further comprising:

the heating device is positioned in the process chamber and used for heating the temperature in the process chamber to the process temperature required by the deposition of the polycrystalline silicon thin film;

the exhaust device is communicated with the inside of the process chamber and is used for controlling the pressure in the process chamber to be a preset pressure when the polycrystalline silicon film deposition is carried out; and

and the back pressure gas supply device is communicated with the inside of the process chamber and is used for providing back pressure gas in the process chamber after the deposition of the polycrystalline silicon film is finished.

4. The polysilicon thin film deposition system of claim 1, wherein the process chamber is located above the wafer loading chamber, the polysilicon thin film deposition system further comprising:

the wafer boat is positioned in the wafer loading chamber and used for loading the wafers; and

and the driving device is connected with the wafer boat and used for driving the wafer boat to drive the wafers to be transmitted between the wafer loading chamber and the process chamber.

5. The polysilicon thin film deposition system of claim 4, further comprising:

the wafer bearing platform is positioned outside the wafer device chamber, communicated with the wafer loading chamber and used for bearing a wafer box;

and the mechanical arm is positioned in the wafer loading chamber and used for transferring the wafers between the wafer box and the wafer boat.

6. The polysilicon thin film deposition system of claim 5, further comprising:

the process control system is used for establishing a process program and controlling the deposition of the polycrystalline silicon thin film based on the process program; and

and a control device connected to the process control system, the oxygen-containing gas supply device and the shielding gas supply device, for controlling the oxygen-containing gas supply device to supply the oxygen-containing gas into the wafer loading chamber based on the process recipe, and controlling the shielding gas supply device to supply the shielding gas into the wafer loading chamber based on the process recipe.

7. The system of claim 6, wherein the control device controls the oxygen-containing gas supply device to supply the oxygen-containing gas into the wafer loading chamber from any time after the wafer boat transfers all the wafers to the process chamber to the time when the wafer boat transfers all the wafers back to the wafer loading chamber.

8. The polysilicon thin film deposition system according to claim 6, wherein the control device controls the shielding gas supply device to supply the shielding gas into the wafer loading chamber throughout the period from the loading of the wafer cassette into the wafer stage to the unloading of the wafer cassette from the wafer stage.

9. The polysilicon thin film deposition system according to any one of claims 1 to 8, wherein the oxygen-containing gas comprises oxygen and the shielding gas comprises nitrogen.

10. A polycrystalline silicon film deposition method is characterized by comprising the following steps:

introducing protective gas into the wafer loading chamber, and loading the wafer needing polycrystalline silicon film deposition in the wafer loading chamber;

transferring the loaded wafer into a process chamber;

depositing a polycrystalline silicon film on the surface of the wafer; and

after the deposition of the polycrystalline silicon film is finished, the wafer is conveyed back into the wafer loading chamber from the process chamber;

and introducing oxygen-containing gas into the wafer loading chamber at least in the process of transferring the wafer from the process chamber to the wafer loading chamber after the deposition of the polycrystalline silicon film.

11. The method as claimed in claim 10, wherein the oxygen-containing gas is introduced into the wafer loading chamber after all the wafers are transferred to the process chamber.

12. The method as claimed in claim 10, further comprising the step of pumping the pressure in the process chamber to a predetermined pressure at which the polysilicon film is deposited after the wafer is transferred into the process chamber and before the polysilicon film is deposited on the surface of the wafer; and after the deposition of the polycrystalline silicon film is finished, the step of introducing back pressure gas into the process chamber is also included before the wafer is conveyed back into the wafer loading chamber from the process chamber.

13. The method of claim 12, wherein the back pressure gas is introduced into the process chamber while the oxygen-containing gas is introduced into the wafer loading chamber.

14. The method as claimed in claim 10, further comprising the step of suspending the transfer for a predetermined time during the process of transferring the wafer from the process chamber back to the wafer loading chamber.

15. The method according to claim 10, wherein the polysilicon film is deposited on the surface of the wafer after the temperature inside the process chamber is heated to the process temperature; after the wafer is conveyed back into the wafer loading chamber from the process chamber, stopping introducing the oxygen-containing gas into the wafer loading chamber, and continuously introducing the protective gas into the wafer loading chamber while executing the following steps:

cooling the wafer to room temperature; and

and transferring the cooled wafer back to the wafer box.

16. The method of claim 10, wherein the wafers comprise product wafers, process monitor wafers and filler wafers, the wafers are loaded in a boat, the product wafers are located between adjacent process monitor wafers, and the filler wafers are located above the top process monitor wafer and below the bottom process monitor wafer.

17. The method according to any one of claims 10 to 16, wherein the introduction of the protective gas into the wafer loading chamber is stopped when the oxygen-containing gas is introduced into the wafer loading chamber.

18. The method according to any one of claims 10 to 16, wherein the introduction of the protective gas into the wafer loading chamber is continued while the oxygen-containing gas is introduced into the wafer loading chamber.

Technical Field

The invention belongs to the technical field of semiconductor preparation, and particularly relates to a polycrystalline silicon film deposition system and method.

Background

With the development of the semiconductor industry, the requirements of device performance on the process are higher and higher, the deposition of the polycrystalline silicon film is a common semiconductor processing process, and compared with an amorphous silicon film process, the conductivity of the polycrystalline silicon film has great advantage and serves as a lead after being doped.

In the existing polysilicon thin film deposition equipment, air or nitrogen can be continuously introduced into the wafer loading chamber in the whole process of transferring the wafer back to the wafer loading chamber and transferring the wafer back into the wafer box after the deposition of the polysilicon thin film is finished from the time of loading the wafer in the wafer boat, if oxygen does not influence the prior process, air can be introduced into the wafer loading chamber, and if oxygen influences the prior process, nitrogen needs to be introduced into the wafer loading chamber to protect the structure obtained by the prior process. However, since the wafers loaded in the boat include fill wafers and process monitor wafers in addition to product wafers; if air is continuously introduced into the wafer loading chamber, the surface of the filled wafer exposed in the air can be oxidized, the deposition of the polycrystalline silicon film on the surface of the filled wafer becomes nucleation growth, the thicknesses of the previous process and the next process are obviously different, the time of the filled wafer exposed in the air is different, the surface oxidation degree is different, the influence on the next process is different, and the thickness of the polycrystalline silicon film formed on the surface of the product wafer in different batches is unstable and the thickness uniformity is poor due to the influence of the filled wafer; if the nitrogen is continuously introduced into the wafer loading chamber, the polycrystalline silicon on the surface of the filled wafer is not oxidized, the in-situ growth speed is high when the polycrystalline silicon film deposition is carried out, the consumed reaction gas quantity is large, the thickness uniformity of the product wafer and the process monitoring wafer is poor, and the thickness of the polycrystalline silicon film deposited on the surface of the product wafer is influenced; meanwhile, after the deposition of the polysilicon film is performed on the surface of the wafer, the surface of the deposited polysilicon film is not subjected to the oxidation process, and if the subsequent photolithography process is directly performed, the photolithography process is seriously affected, so that the uniformity of the Critical Dimension (CD) of photolithography is deteriorated, and the process needs to be additionally added to ensure the uniformity of the critical dimension of photolithography, thereby increasing the cost.

Disclosure of Invention

In view of the above-mentioned shortcomings of the prior art, it is an object of the present invention to provide a polysilicon thin film deposition system and method, which can solve the above-mentioned problems of the polysilicon thin film deposition system in the prior art due to the fact that only air or nitrogen can be introduced into the wafer loading chamber.

To achieve the above and other related objects, the present invention provides a polysilicon thin film deposition system, comprising:

the wafer loading chamber is used for loading a wafer which needs to be subjected to polycrystalline silicon film deposition;

the process chamber is communicated with the wafer loading chamber and is used for depositing a polycrystalline silicon film on the surface of the loaded wafer;

the oxygen-containing gas supply device comprises an oxygen-containing gas supply pipeline, one end of the oxygen-containing gas supply pipeline extends to the interior of the wafer loading chamber and is used for supplying oxygen-containing gas into the wafer loading chamber at least in the process of transferring the wafers from the process chamber into the wafer loading chamber after the deposition of the polycrystalline silicon thin film; and

and the protective gas supply device comprises a protective gas supply pipeline, one end of the protective gas supply pipeline extends to the interior of the wafer loading chamber and is used for supplying protective gas into the wafer loading chamber at least when the oxygen-containing gas supply device does not supply the oxygen-containing gas into the wafer loading chamber.

Optionally, the polysilicon thin film deposition system further comprises a baffle plate located between the wafer loading chamber and the process chamber for isolating the wafer loading chamber from the process chamber before and after the transfer of the wafer to the process chamber.

Optionally, the polysilicon thin film deposition system further comprises:

the heating device is positioned in the process chamber and used for heating the temperature in the process chamber to the process temperature required by the deposition of the polycrystalline silicon thin film;

the exhaust device is communicated with the inside of the process chamber and is used for controlling the pressure in the process chamber to be a preset pressure when the polycrystalline silicon film deposition is carried out; and

and the back pressure gas supply device is communicated with the inside of the process chamber and is used for providing back pressure gas in the process chamber after the deposition of the polycrystalline silicon film is finished.

Optionally, the process chamber is located above the wafer loading chamber, and the polysilicon thin film deposition system further includes:

the wafer boat is positioned in the wafer loading chamber and used for loading the wafers; and

and the driving device is connected with the wafer boat and used for driving the wafer boat to drive the wafers to be transmitted between the wafer loading chamber and the process chamber.

Optionally, the polysilicon deposition system further comprises:

the wafer bearing platform is positioned at the outer side of the wafer loading chamber, is communicated with the wafer loading chamber and is used for bearing a wafer box;

and the mechanical arm is positioned in the wafer loading chamber and used for transferring the wafers between the wafer box and the wafer boat.

Optionally, the polysilicon thin film deposition system further comprises:

the process control system is used for establishing a process program and controlling the deposition of the polycrystalline silicon thin film based on the process program; and

and a control device connected to the process control system, the oxygen-containing gas supply device and the shielding gas supply device, for controlling the oxygen-containing gas supply device to supply the oxygen-containing gas into the wafer loading chamber based on the process recipe, and controlling the shielding gas supply device to supply the shielding gas into the wafer loading chamber based on the process recipe.

Optionally, the control device controls the oxygen-containing gas supply device to supply the oxygen-containing gas into the wafer loading chamber from any time after the wafer boat transfers all the wafers to the process chamber during the process of transferring all the wafers back to the wafer loading chamber by the wafer boat.

Optionally, the control device controls the protective gas supply device to supply the protective gas into the wafer loading chamber during the whole process from the loading of the wafer cassette into the wafer loading table to the unloading of the wafer cassette from the wafer loading table.

Optionally, the oxygen-containing gas comprises oxygen and the shielding gas comprises nitrogen.

The invention also provides a polycrystalline silicon film deposition method, which comprises the following steps:

introducing protective gas into the wafer loading chamber, and loading the wafer needing polycrystalline silicon film deposition in the wafer loading chamber;

transferring the loaded wafer into a process chamber;

depositing a polycrystalline silicon film on the surface of the wafer; and

after the deposition of the polycrystalline silicon film is finished, the wafer is conveyed back into the wafer loading chamber from the process chamber;

and introducing oxygen-containing gas into the wafer loading chamber at least in the process of transferring the wafer from the process chamber to the wafer loading chamber after the deposition of the polycrystalline silicon film.

Optionally, the oxygen-containing gas is introduced into the wafer loading chamber after all the wafers are transferred to the process chamber.

Optionally, the method further includes, after the wafer is transferred into the process chamber and before the deposition of the polysilicon thin film is performed on the surface of the wafer, pumping the pressure in the process chamber to a preset pressure, and performing the deposition of the polysilicon thin film under the preset pressure; and after the deposition of the polycrystalline silicon film is finished, the step of introducing back pressure gas into the process chamber is also included before the wafer is conveyed back into the wafer loading chamber from the process chamber.

Optionally, the back pressure gas is introduced into the process chamber while the oxygen-containing gas is introduced into the wafer loading chamber.

Optionally, the process of transferring the wafer from the process chamber back into the wafer loading chamber further includes a step of suspending the transfer for a predetermined time.

Optionally, heating the temperature inside the process chamber to a process temperature, and then performing polycrystalline silicon thin film deposition on the surface of the wafer; after the wafer is conveyed back into the wafer loading chamber from the process chamber, stopping introducing the oxygen-containing gas into the wafer loading chamber, and continuously introducing the protective gas into the wafer loading chamber while executing the following steps:

cooling the wafer to room temperature; and

and transferring the cooled wafer back to the wafer box.

Optionally, the wafers include product wafers, process monitor wafers, and filler wafers, the wafers are loaded in a wafer boat, the product wafers are located between adjacent process monitor wafers, and the filler wafers are located above the top process monitor wafer and below the bottom process monitor wafer.

Optionally, the introduction of the protective gas into the wafer loading chamber is stopped when the oxygen-containing gas is introduced into the wafer loading chamber.

Optionally, the protective gas is continuously introduced into the wafer loading chamber while the oxygen-containing gas is introduced into the wafer loading chamber.

As mentioned above, the polysilicon film deposition system and method of the present invention have the following advantages: according to the polycrystalline silicon film deposition system, the oxygen-containing gas supply device and the protective gas supply device which are communicated with the interior of the wafer loading chamber are arranged, so that oxygen-containing gas can be supplied into the wafer loading chamber by the oxygen-containing gas supply device at least in the process of conveying the wafer from the process chamber into the wafer loading chamber after the polycrystalline silicon film is deposited, the surface of the polycrystalline silicon film deposited on the surface of the wafer can be oxidized, the adverse effect on the subsequent photoetching process is avoided, and the key size of the subsequent photoetching process is ensured to have better uniformity; meanwhile, the protective gas supply device can be used for supplying protective gas into the wafer loading chamber at least when the oxygen-containing gas supply device does not supply the oxygen-containing gas into the wafer loading chamber, so that the surface of the filled wafer can be protected from being oxidized before the deposition of the polycrystalline silicon film, and the next process is not influenced by the previous process;

the polycrystalline silicon film deposition method can ensure that the surface of the polycrystalline silicon film deposited on the surface of the wafer is oxidized, avoid the adverse effect on the subsequent photoetching process and ensure that the key dimension of the subsequent photoetching process has better uniformity by providing the oxygen-containing gas into the wafer loading chamber at least in the process of conveying the wafer from the process chamber into the wafer loading chamber after the polycrystalline silicon film is deposited; meanwhile, the protective gas is provided in the wafer loading chamber at least when the oxygen-containing gas is not provided in the wafer loading chamber, so that the surface of the filled wafer can be protected from being oxidized before the deposition of the polycrystalline silicon film, and the previous process can not influence the next process.

Drawings

Fig. 1 and fig. 2 are schematic structural diagrams of a polysilicon thin film deposition system provided in an embodiment of the present invention under different working conditions, where fig. 1 is a schematic structural diagram of a boat loaded with wafers before polysilicon thin film deposition in a state of being transferred from a wafer loading chamber to a process chamber, and fig. 2 is a schematic structural diagram of a boat loaded with wafers after polysilicon thin film deposition in a state of being transferred from the process chamber to the wafer loading chamber.

Fig. 3 is a schematic structural diagram illustrating a wafer boat loaded with wafers in the polysilicon thin film deposition system according to an embodiment of the present invention.

Fig. 4 is a flowchart illustrating a polysilicon thin film deposition method according to another embodiment of the present invention.

Description of the element reference numerals

1 wafer Loading Chamber

2 Process Chamber

3 oxygen-containing gas supply line

4 protective gas supply line

5 wafer

51 filling wafer

52 Process monitoring wafer

53 product wafer

6 boat

S1-S4

Detailed Description

The embodiments of the present invention are described below with reference to specific embodiments, and other advantages and effects of the present invention will be easily understood by those skilled in the art from the disclosure of the present specification. The invention is capable of other and different embodiments and of being practiced or of being carried out in various ways, and its several details are capable of modification in various respects, all without departing from the spirit and scope of the present invention.

Please refer to fig. 1 to 4. It should be noted that the drawings provided in the present embodiment are only schematic and illustrate the basic idea of the present invention, and although the drawings only show the components related to the present invention and are not drawn according to the number, shape and size of the components in actual implementation, the form, quantity and proportion of the components in actual implementation may be changed arbitrarily, and the layout of the components may be more complicated.