CN217438298U

CN217438298U - Epitaxial growth equipment

Info

Publication number: CN217438298U
Application number: CN202221338267.8U
Authority: CN
Inventors: 丁肇诚; 吕理宏; 王怀義; 范一龙
Original assignee: Baohong Technology Co ltd
Current assignee: Baohong Technology Co ltd
Priority date: 2022-05-31
Filing date: 2022-05-31
Publication date: 2022-09-16
Anticipated expiration: 2032-05-31

Abstract

An epitaxial growth apparatus includes a chamber, a gas nozzle and a carrier plate. The gas nozzle is arranged at the top in the cavity and comprises an annular gas spraying part, a central gas spraying part and an annular gas extraction part, wherein the central gas spraying part is positioned in the annular gas spraying part, and the annular gas extraction part is positioned between the annular gas spraying part and the central gas spraying part. The bearing plate is arranged in the cavity and positioned below the gas nozzle, and the bearing plate is configured to bear a substrate to be grown with epitaxy.

Description

Epitaxial growth equipment

Technical Field

The present invention relates to semiconductor processing equipment, and more particularly to epitaxial growth equipment.

Background

Epitaxy (epitoxy) is one of the common techniques used in semiconductor device fabrication, in which a new semiconductor layer is obtained by growing or depositing a new crystal on an original wafer. Epitaxial techniques can be used to fabricate various semiconductor devices, particularly wafers for compound semiconductors. Common epitaxial techniques include Physical Vapor Deposition (PVD) and Chemical Vapor Deposition (CVD), wherein a thin film is deposited on a substrate by Chemical reaction of process gases.

In chemical vapor deposition, a plurality of byproducts (or exhaust gas) are generated during the chemical reaction process to affect the epitaxial growth, and the conventional process is to use an air pumping device to pump the byproducts out of the reaction chamber, such as taiwan patent publications TW I746222B, TWI480417B, and taiwan patent publication TW 202104650A. However, it is still difficult for the conventional epitaxial growth apparatus to effectively remove the byproducts, so that the byproducts remain or diffuse into the reaction region to affect the quality of the epitaxial growth. Therefore, how to effectively remove the by-products generated by the chemical reaction of the process gases in the epitaxial growth equipment is a problem to be solved by those skilled in the art.

SUMMERY OF THE UTILITY MODEL

The present invention is directed to a semiconductor epitaxial device for removing waste gas and by-product with poor efficiency.

To achieve the above object, the present invention provides an epitaxial growth apparatus, which comprises a chamber, a gas nozzle and a susceptor. The gas nozzle is arranged at the top in the cavity and comprises an annular gas spraying part, a central gas spraying part and an annular gas extraction part, wherein the central gas spraying part is positioned in the annular gas spraying part, and the annular gas extraction part is positioned between the annular gas spraying part and the central gas spraying part. The bearing plate is arranged in the cavity and positioned below the gas sprayer, and the bearing plate is configured to bear a substrate to be grown with epitaxy. The annular gas spraying part provides a downward annular gas curtain, the central gas spraying part provides a downward process gas, the cavity defines a non-epitaxial growth area and an epitaxial growth area corresponding to the annular gas curtain and the process gas, and the annular gas pumping part pumps the epitaxial growth area between the annular gas spraying part and the central gas spraying part so as to pump the waste gas generated during the substrate growth epitaxy away from the epitaxial growth area.

In one embodiment, the epitaxial growth apparatus further includes a heater disposed in the chamber and under the susceptor.

In an embodiment, the epitaxial growth apparatus further includes a vacuum pumping device, and the vacuum pumping device is connected to the chamber.

In one embodiment, the central injection portion and the annular injection portion respectively include a plurality of injection holes, and the annular pumping portion includes a plurality of pumping holes.

Therefore, the utility model discloses an epitaxial growth equipment utilizes this processing procedure gas of the gaseous portion supply of this central authorities of jet-propelled portion, through this annular air curtain of the gaseous time and the concentration that stops in this epitaxial growth district of this processing procedure of this annular air curtain supply, promotes the quality of epitaxy, and the by-product that produces after carrying out chemical reaction with this processing procedure gas by this annular portion of bleeding is taken out from this epitaxial growth district at last. The annular air exhaust part is arranged between the central air injection part and the annular air injection part and corresponds to the epitaxial growth area, and the air exhaust efficiency can be greatly increased. Therefore, the utility model discloses a before this epitaxy growth equipment can waft the accessory substance to this non-epitaxy growth district, take out this cavity with it effectively, provide cleaner deposition environment of this base plate.

Drawings

Fig. 1 is a schematic structural diagram of an embodiment of the present invention;

fig. 2 is a schematic bottom view of a gas shower according to an embodiment of the present invention;

fig. 3A to 3C are schematic airflow diagrams of a gas showerhead according to an embodiment of the present invention.

[ notation ] to show

10: cavity body

11: epitaxial growth region

12: non-epitaxial growth region

20: gas nozzle

21: central air jet part

211: gas injection hole

22: annular air extraction part

221: air extraction hole

23: annular air injection part

231: gas injection hole

21 a: process gas

22 a: air flow of the exhaust

23 a: annular air curtain

30: bearing plate

40: heating device

50: vacuum air extractor

51: air extraction pipeline

60: substrate

Detailed Description

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms "a", "an" and "the" may include the plural forms as well, unless the context indicates otherwise.

Directional phrases used herein, such as, for example, upper, lower, left, right, front, back, and derivatives thereof, relate to the orientation of the elements in the drawings and are not limiting upon the invention unless the context clearly dictates otherwise. The detailed description and technical contents of the present invention will now be described with reference to the drawings as follows:

referring to fig. 1, the present invention discloses an epitaxial growth apparatus, which includes a chamber 10, a gas nozzle 20, a susceptor 30, a heater 40, and a vacuum pumping device 50. The gas nozzle 20 is disposed in the chamber 10 and located at a top of the chamber 10, the gas nozzle 20 includes a central gas injection portion 21, an annular gas exhaust portion 22 and an annular gas injection portion 23, the central gas injection portion 21 is located in the annular gas injection portion 23, and the annular gas exhaust portion 22 is located between the annular gas injection portion 23 and the central gas injection portion 21.

As shown in fig. 2, which is a schematic bottom view of the gas shower head according to an embodiment of the present invention, the central gas injection portion 21, the annular gas exhaust portion 22 and the annular gas injection portion 23 are sequentially arranged from a center of the gas shower head 20 to an outside. The central air injection portion 21 and the annular air injection portion 23 have a plurality of

air injection holes

211 and 231, respectively, and the annular air extraction portion 22 has a plurality of air extraction holes 221. The air injection holes 211 of the central air injection portion 21 are arranged in a circular pattern, the air injection holes 221 of the annular air exhaust portion 22 are arranged in a first annular pattern, and the air injection holes 231 of the annular air injection portion 23 are arranged in a second annular pattern. In some embodiments, the gas injection holes 211 of the central gas injection portion 21 may be arranged in a circular array, a rectangular array, or in other patterns. The air exhaust holes 221 of the annular air exhaust portion 22 and the air injection holes 231 of the annular air injection portion 23 may be arranged at equal intervals or at unequal intervals.

Returning to fig. 1, the susceptor 30 is disposed in the chamber 10 below the gas showerhead 20, and the susceptor 30 carries a substrate 60 to be epitaxially grown. The heater 40 is disposed in the chamber 10 and under the susceptor 30 for heating the substrate 60. The vacuum pumping device 50 is disposed outside the chamber 10 and connected to the chamber 10 through a pumping line 51, and the vacuum pumping device 50 pumps air into the chamber 10 before the process starts to form a vacuum state inside the chamber 10.

An epitaxial growth region 11 is correspondingly defined below the central gas injection portion 21, a non-epitaxial growth region 12 is defined outside the epitaxial growth region 11, the central gas injection portion 21 provides a downward-blowing process gas 21a (as shown in fig. 3A), and the process gas 21a is configured to cover the substrate 60 or a central area of the substrate 60 according to different processes. The annular gas spraying portion 23 provides an annular gas curtain 23a (as shown in fig. 3B) blown downward, and the annular gas curtain 23a is configured to cover an outer ring area of the substrate 60 or an outer ring area outside the substrate 60 according to the process. The annular gas curtain 23a can be used as an annular barrier to prevent the process gas 21a from overflowing and to prevent external contaminants or impurities from entering the epitaxial growth region 11.

In the present invention, the annular air exhaust portion 22, the annular air injection portion 23 and the central air injection portion 21 are commonly disposed on the gas nozzle 20 and located above the substrate 60, thereby providing an upward air exhaust flow 22a (as shown in fig. 3C). And the annular pumping part 22 is located between the annular spraying part 23 and the central spraying part 21 when viewed from a plane, so that the annular pumping part 22 is directly adjacent to the central spraying part 21 rather than outside the annular spraying part 23, thereby more efficiently pumping out the by-products or exhaust gas generated by the chemical reaction of the process gas 21 a. On the other hand, the utility model adopts the top suction mode to extract the by-product or waste gas by using the extraction airflow 22 a; instead of pumping laterally, the byproducts or exhaust gases generated in the epitaxial growth region 11 need to pass through the annular gas curtain 23a to be pumped away, which is inefficient and can damage the gas flow structure of the annular gas curtain 23 a. In addition, since the annular pumping portion 22, the annular gas injection portion 23 and the central gas injection portion 21 are commonly located above the substrate 60, the pumping gas flow 22a, the annular gas curtain 23a and the processing gas 21a are in opposite directions, and the pumping gas flow 22a has little influence on the gas flows of the annular gas curtain 23a and the processing gas 21a, so as to ensure that each gas flow plays a separate function in the epitaxial process.

Further, the central gas injection portion 21 injects the process gas 21a downward toward the substrate 60, and the process gas 21a may be silane vapor (SiH) ₄ ) Silane vapor (SiH) ₄ ) And oxygen (O) ₂ ) Mixture of (3), silane vapor (SiH) ₄ ) And ammonia (NH) ₃ ) Mixtures of (A) and (B), metal halides (e.g. WF) ₆ ) Or a mixture of a metal halide and hydrogen. Meanwhile, the annular gas spraying portion 23 provides the annular gas curtain 23a blowing downward and generates a boundary layer (boundary layer) to block the process gas 21a from overflowing, and the annular gas curtain 23a may be an inert gas including, but not limited to, nitrogen, helium, argon, or the like.

In detail, the cavity 10 defines the epitaxial growth region 11 corresponding to the process gas 21a, the cavity 10 defines the non-epitaxial growth region 12 corresponding to the annular gas curtain 23a, the process gas 21a chemically reacts in the epitaxial growth region 11 and deposits on the substrate 60, and the annular gas curtain 23a prevents the process gas 21a from flowing out of the epitaxial growth region 11 to the non-epitaxial growth region 12, so as to increase the time and concentration of the process gas 21a staying in the epitaxial growth region 11, so that the process gas 21a can sufficiently chemically react and deposit on the surface of the substrate 60, thereby effectively improving the quality and uniformity of epitaxy.

During the chemical reaction of the process gas 21a in the epitaxial growth region 11, a byproduct (e.g., exhaust gas, the incompletely reacted process gas 21a) is generated after the chemical reaction, and if the byproduct stays in the epitaxial growth region 11 for a long time, the uniformity and effectiveness of the process gas 21a deposited on the substrate 60 will be affected. Therefore, while the central gas injection part 21 provides the downward blowing process gas 21a and the annular gas injection part 23 provides the downward blowing annular gas curtain 23a, the annular gas exhaust part 22 exhausts the epitaxial growth region 11 to exhaust the byproducts generated during the epitaxial growth of the substrate 60 from the epitaxial growth region 11, so as to prevent the byproducts from affecting the uniformity and effectiveness of the deposition of the process gas 21a on the substrate 60. On the other hand, the annular pumping part 22 is disposed between the central gas injection part 21 and the annular gas injection part 23 within the non-epitaxial growth region 12, so that the by-products can be effectively pumped out of the epitaxial growth region 11 by the annular pumping part 22 before being diffused outward into the non-epitaxial growth region 12. In other words, by disposing the annular pumping part 22, the by-products can be effectively prevented from flowing back to the epitaxial growth region 11 or floating to other regions of the chamber 10.

To sum up, the utility model discloses an epitaxial growth equipment sets up in the top of bearing dish and base plate through annular portion of bleeding, provides the air current of bleeding of vertical direction, because annular portion of bleeding disposes between annular portion of bleeding and central portion of spouting, the air current of bleeding consequently can contact epitaxial growth district and directly upwards takes out from epitaxial growth district accessory substance or waste gas. In contrast, in the prior art, the by-products or exhaust gases are extracted from the outside of the air curtain, and the by-products or exhaust gases need to pass through the air curtain, so that the by-products or exhaust gases may be blocked and not effectively carried away, in addition to destroying the flow structure of the air curtain. Therefore, the utility model discloses an annular portion of bleeding can be more efficient and take out the accessory substance or the waste gas that produce after carrying out the chemical reaction with the processing procedure gas fast and leave epitaxial growth district and can not be along with the air current diffusion wantonly in the epitaxial growth district, also can not fly away to outside the non-epitaxial growth district and pollute the environment in the cavity.

Claims

1. An epitaxial growth apparatus, comprising:

a cavity;

the gas nozzle is arranged at the top in the cavity and comprises an annular gas spraying part, a central gas spraying part and an annular gas extraction part, wherein the central gas spraying part is positioned in the annular gas spraying part, and the annular gas extraction part is positioned between the annular gas spraying part and the central gas spraying part; and

the bearing disc is arranged in the cavity and positioned below the gas spray head, and is configured to bear a substrate to be subjected to epitaxial growth;

the annular gas spraying part provides a downward annular gas curtain, the central gas spraying part provides a downward process gas, the cavity defines a non-epitaxial growth area and an epitaxial growth area corresponding to the annular gas curtain and the process gas, and the annular gas pumping part pumps the epitaxial growth area between the annular gas spraying part and the central gas spraying part so as to pump the waste gas generated during the substrate growth epitaxy away from the epitaxial growth area.

2. The epitaxial growth apparatus of claim 1, further comprising a heater disposed in the chamber below the susceptor.

3. The epitaxial growth apparatus of claim 1, further comprising a vacuum pumping device connected to the chamber.

4. The epitaxial growth apparatus of claim 1, wherein the central gas injection portion and the annular gas injection portion respectively comprise a plurality of gas injection holes, and the annular gas extraction portion comprises a plurality of gas extraction holes.