A plasma enhanced space atomic layer deposition device

Abstract

The present invention is a plasma enhanced space atomic layer deposition device, in which a uniform flow assembly composed of multiple uniform flow units is installed in a process chamber, different reaction gases are provided at different spatial positions in the process chamber, and different reaction gases are isolated by inert gas. The silicon wafer to be processed is placed on a silicon wafer carrier, and the silicon wafer carrier is driven by the module to swing back and forth at different reaction gas outlets of the uniform flow assembly. Each time a reaction gas outlet is passed, a layer of atomic layer of reaction gas will be covered on the surface of the silicon wafer; the number and speed of swings of the silicon wafer carrier are controlled according to production needs, so as to effectively control the coating thickness on the surface of the silicon wafer. By controlling the vacuum pump, the process gas remaining in the reaction in the furnace chamber can be extracted.

Description

Technical Field

[0001] The present invention relates to an atomic layer deposition device, in particular to a plasma enhanced space type atomic layer deposition device. Background Art

[0002] In conventional atomic layer deposition (ALD), precursors are sequentially exposed to the substrate via short pulses while being kept physically separated by intermediate purge steps. Spatial ALD (SALD) is a variation of ALD in which precursors are supplied continuously at different locations and are kept separated by inert gas zones or regions. Film growth is achieved by exposing the substrate to locations containing different precursors. Since the purge step is eliminated, the process becomes faster, effectively increasing the deposition rate.

[0003] In addition, several existing technical research documents at home and abroad show that compared with thermal atomic layer deposition (T-ALD), the use of plasma (Dielectric Barrier Discharge, DBD) assisted atomic layer deposition technology can achieve atomic layer deposition of organic, inorganic or metal films at a lower temperature, and can obtain a higher film deposition rate and a shorter rinsing time. And some existing technical research documents show that the atmospheric pressure DBD plasma assisted deposition of Al2O3 film has ALD growth characteristics, with a growth rate of 0.27nm / cycle, which is higher than the growth rate of Al2O3 deposited by plasma assisted ALD at low pressure; the grown aluminum oxide film has a dense structure, small surface roughness, and a relatively pure film composition; its water vapor transmission rate (WVTR) is reduced from 3.17g / (m~2·d) of the original PET film to 0.05g / (m~2·d).

[0004] However, in the prior art atomic layer deposition equipment, the reaction gas is generally the same at different spatial positions in the process chamber, resulting in the inability to effectively control the coating thickness on the surface of the silicon wafer, affecting the stability of production quality. Summary of the invention

[0005] The present invention proposes a plasma enhanced space atomic layer deposition device, the purpose of which is to overcome the above-mentioned shortcomings of the prior art and achieve effective control of the coating thickness on the surface of the silicon wafer.

[0006] The technical solution of the present invention is: a plasma enhanced space atomic layer deposition equipment, which includes a process chamber, a uniform flow component, a plasma generator, a silicon wafer carrier, a heating plate, a carrier drive module, a vacuum pump and a vacuum baffle valve, wherein a uniform flow component is arranged in the process chamber, one side of the process chamber is connected to the vacuum pump through a pipeline with a vacuum baffle valve, the pipeline connects the process chamber and one side of the uniform flow component, the other side of the uniform flow component is connected to the plasma generator, the first reaction gas supply device, the second reaction gas supply device and the inert gas supply device, a heating plate is arranged between the bottom of the process chamber and the bottom of the uniform flow component, a carrier drive module is arranged outside the process chamber, the output end of the carrier drive module is connected to the silicon wafer carrier in the process chamber, and the silicon wafer carrier reciprocates horizontally between the uniform flow component and the heating plate. The uniform flow component is used to uniformly flow the process gas and plasmatize the process gas. The silicon wafer carrier is used to load the silicon wafer to be coated and move back and forth in the process chamber. The uniform flow component provides different reaction gases at different spatial positions in the process chamber and isolates the different reaction gases through inert gases. The silicon wafer passes through the reaction gas outlet in turn to be covered with an atomic layer of reaction gas on the surface of the silicon wafer; the coating thickness on the surface of the silicon wafer can be effectively controlled.

[0007] Preferably, the flow uniforming assembly includes several groups of flow uniforming units arranged in horizontal sequence, each flow uniforming unit includes five pairs of partition plates arranged in horizontal sequence, an air duct is formed between each pair of partition plates, the positive electrode and the negative electrode pass through the upper parts of all the partition plates at horizontal intervals, each group of flow uniforming units is composed of the fourth pair of partition plates on the side close to the carrier driving module, which are respectively a negative electrode plate and a positive electrode plate, the negative electrode plate and the positive electrode plate are connected to an insulating plate on the side away from the carrier driving module, and a first reaction gas inlet channel and a second reaction gas inlet channel passing through all the partition plates are arranged below the positive electrode, the lower part of the first reaction gas inlet channel is communicated with the air duct between the second pair of partition plates on the side close to the carrier driving module, the lower part of the second reaction gas inlet channel is communicated with the air duct between the negative electrode plate and the positive electrode plate, the first reaction gas inlet channel and the second reaction gas inlet channel are connected to a first reaction gas supply device and a second reaction gas supply device respectively, and the positive electrode and the negative electrode are connected to a plasma generator. The second reaction gas passes through the gas channel between the positive electrode plate and the negative electrode plate and is ionized to generate plasma; the charged plasma is more easily adsorbed on the surface of the silicon wafer, making its reaction more uniform and the film thickness more uniform.

[0008] Preferably, adjacent pairs of partition plates are surrounded by a gas extraction gap, a gas extraction channel passing through all the partition plates is provided between the first reaction gas inlet channel and the positive electrode, the lower part of the gas extraction channel is connected to all the gas extraction gaps, and the gas extraction channel is connected to a pipeline with a vacuum baffle valve. Excess reaction gas after adsorption by the silicon wafer can be extracted to prevent the dust generated in the cavity from polluting the silicon wafer.

[0009] Preferably, an inert gas inlet passage passing through all partition plates is provided between the first reaction gas inlet passage and the exhaust passage, the lower part of the inert gas inlet passage is connected to the air passage between the first, third and fifth pairs of partition plates on the side close to the carrier drive module, and the inert gas inlet passage is connected to the inert gas supply device. Inert gas blowing ports are arranged before the two reaction gas outlets to completely isolate the two reaction gases in space, so as to prevent CVD reaction from occurring on the surface of the silicon wafer, resulting in a thick coating thickness on the surface of the silicon wafer.

[0010] The advantages of the present invention are as follows: the structural design is reasonable. By adding a uniform flow component in the process chamber, different reaction gases can be provided at different spatial positions in the process chamber, and different reaction gases can be isolated by inert gas. The silicon wafer that needs to be processed is driven by the silicon wafer carrier driven by the module to swing back and forth at different reaction gas outlets of the uniform flow component, and a layer of atomic layer of reaction gas can be covered on the surface of the silicon wafer by passing through the reaction gas outlet in turn; the coating thickness on the surface of the silicon wafer can be effectively controlled. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a schematic structural diagram of the plasma enhanced space atomic layer deposition equipment of the present invention.

[0012] Figure 2 yes Figure 1 Schematic diagram of the structure of the flow uniformity component.

[0013] In the figure, 1 is a process chamber, 2 is a uniform flow component, 21 is a partition plate, 211 is an air channel, 22 is a positive electrode, 221 is a positive electrode plate, 23 is a negative electrode, 231 is a negative electrode plate, 24 is an insulating plate, 25 is a first reaction gas inlet channel, 26 is a second reaction gas inlet channel, 27 is an inert gas inlet channel, 28 is an exhaust channel, 281 is an exhaust gap, 3 is a plasma generator, 4 is a silicon wafer carrier, 5 is a heating plate, 6 is a carrier drive module, 7 is a vacuum pump, and 8 is a vacuum baffle valve. DETAILED DESCRIPTION

[0014] The present invention is further described in detail below with reference to examples and specific implementation modes.

[0015] like Figure 1As shown, a plasma enhanced space atomic layer deposition equipment, whose structure includes a process chamber 1, a uniform flow component 2, a plasma generator 3, a silicon wafer carrier 4, a heating plate 5, a carrier drive module 6, a vacuum pump 7 and a vacuum baffle valve 8, wherein the uniform flow component 2 is arranged in the process chamber 1, one side of the process chamber 1 is connected to the vacuum pump 7 through a pipeline with a vacuum baffle valve 8, the pipeline connects the process chamber 1 and one side of the uniform flow component 2, the other side of the uniform flow component is connected to the plasma generator 3, a first reaction gas supply device, a second reaction gas supply device and an inert gas supply device, a heating plate 5 is arranged between the bottom of the process chamber 1 and the bottom of the uniform flow component 2, a carrier drive module 6 is arranged outside the process chamber 1, the output end of the carrier drive module 6 is connected to the silicon wafer carrier 4 in the process chamber 1, and the silicon wafer carrier 4 reciprocates horizontally between the uniform flow component 2 and the heating plate 5.

[0016] The process chamber 1 provides the vacuum and high temperature environment required for the coating process.

[0017] The flow-uniform component 2 is used to uniformly flow the process gas and plasmatize the process gas.

[0018] The plasma generator 3 electrolyzes the process gas into plasma.

[0019] The silicon wafer carrier 4 is used to carry the silicon wafer to be coated and moves back and forth in the process chamber 1 .

[0020] The heating plate 5 provides the required temperature environment for the atomic layer deposition process.

[0021] The carrier driving module 6 is used to drive the silicon wafer carrier 4 to move back and forth in the process chamber 1 .

[0022] The vacuum pump 7 evacuates the process chamber and removes excess process gas.

[0023] The vacuum baffle valve 8 controls the on-off between the vacuum pump 7 and the process chamber 1 .

[0024] like Figure 2As shown, the uniform flow assembly 2 includes a plurality of groups of uniform flow units arranged in a horizontal order, each uniform flow unit includes five pairs of partition plates 21 arranged in a horizontal order, each pair of partition plates 21 forms an air channel 211, and adjacent pairs of partition plates 21 form an exhaust gap 281, and the positive electrode 22 and the negative electrode 23 pass through the upper part of all the partition plates 21 at intervals. Each group of uniform flow units is composed of a fourth pair of partition plates 21 on the side close to the carrier drive module 6, which are respectively a negative electrode plate 231 and a positive electrode plate 221, and the negative electrode plate 231 and the positive electrode plate 221 are connected to an insulating plate 24 away from the carrier drive module 6. An exhaust duct 28, an inert gas inlet duct 27, a first reaction gas inlet duct 25, and a second reaction gas inlet duct 26 passing through all the partition plates 21 are arranged below the positive electrode 22. The exhaust duct 2 The lower part of 8 is communicated with all the exhaust gaps 281, the lower part of the inert gas inlet channel 27 is communicated with the air channel 211 between the first, third and fifth pairs of partition plates 21 on the side close to the carrier driving module 6, the lower part of the first reaction gas inlet channel 25 is communicated with the air channel 211 between the second pair of partition plates 21 on the side close to the carrier driving module 6, the lower part of the second reaction gas inlet channel 26 is communicated with the air channel 211 between the negative electrode plate 231 and the positive electrode plate 221, the exhaust channel 28, the inert gas inlet channel 27, the first reaction gas inlet channel 25 and the second reaction gas inlet channel 26 are respectively connected to the pipeline with the vacuum baffle valve 8, the inert gas supply device, the first reaction gas supply device and the second reaction gas supply device, and the positive electrode 22 and the negative electrode 23 are connected to the plasma generator 3.

[0025] The uniform flow component 2 is provided with 3 air inlets, 2 of which are for reaction gas inlets and 1 is for inert gas inlet; and a gas extraction port is provided to extract excess reaction gas.

[0026] The second reaction gas passes through the gap (gas channel 211) between the positive electrode plate 221 and the negative electrode plate 231 and is ionized to generate plasma; the charged plasma is more easily adsorbed on the surface of the silicon wafer, making its reaction more uniform and the film thickness more uniform.

[0027] Both sides of the two reaction gas outlets are provided with exhaust ports (exhaust gaps 281), which can extract excess reaction gas after adsorption by the silicon wafer to prevent dust generated in the chamber from contaminating the silicon wafer.

[0028] Inert gas blowing ports are arranged before the two reaction gas outlets to completely isolate the two reaction gases in space and prevent CVD reaction (chemical vapor deposition) from occurring on the surface of the silicon wafer, which would result in a thicker coating thickness on the surface of the silicon wafer.

[0029] According to the above structure, a flow-uniform component 2 composed of multiple flow-uniform units is installed in the process chamber 1, and different reaction gases are provided at different spatial positions in the process chamber 1, and different reaction gases are isolated by inert gas. The silicon wafer to be processed is placed on the silicon wafer carrier 4, and the silicon wafer carrier 4 is driven by the module to swing back and forth at different reaction gas outlets of the flow-uniform component 2. Every time a reaction gas outlet is passed, a layer of atomic layer of reaction gas will be covered on the surface of the silicon wafer; the number and speed of swings of the silicon wafer carrier 4 are controlled according to production needs, and the coating thickness on the surface of the silicon wafer can be effectively controlled. And by controlling the vacuum pump 7, the process gas remaining in the reaction in the furnace chamber can be extracted.

[0030] The above is only a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several modifications and improvements without departing from the inventive concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A plasma enhanced space atomic layer deposition device, characterized in that: The invention comprises a process chamber (1), a flow-uniform component (2), a plasma generator (3), a silicon wafer carrier (4), a heating plate (5), a carrier drive module (6), a vacuum pump (7) and a vacuum baffle valve (8), wherein the flow-uniform component (2) is arranged in the process chamber (1), one side of the process chamber (1) is connected to the vacuum pump (7) via a pipeline with a vacuum baffle valve (8), the pipeline is connected to the process chamber (1) and one side of the flow-uniform component (2), the other side of the flow-uniform component is connected to the plasma generator (3), a first reaction gas supply device, a second reaction gas supply device and an inert gas supply device, a heating plate (5) is arranged between the bottom of the process chamber (1) and the bottom of the flow-uniform component (2), a carrier drive module (6) is arranged outside the process chamber (1), the output end of the carrier drive module (6) is connected to the silicon wafer carrier (4) in the process chamber (1), and the silicon wafer carrier (4) reciprocates horizontally between the flow-uniform component (2) and the heating plate (5).

2. The plasma enhanced spatial atomic layer deposition device according to claim 1, characterized in that: The flow-uniform component (2) comprises a plurality of groups of flow-uniform units arranged in a horizontal sequence, each flow-uniform unit comprising five pairs of partition plates (21) arranged in a horizontal sequence, each pair of partition plates (21) forming an airway (211), the positive electrode (22) and the negative electrode (23) passing through the upper part of all the partition plates (21) at intervals in a horizontal direction, each group of flow-uniform units comprising a fourth pair of partition plates (21) on the side close to the carrier drive module (6) comprising a negative electrode plate (231) and a positive electrode plate (221), the negative electrode plate (231) and the positive electrode plate (221) being connected to an insulating plate (24) on the side away from the carrier drive module (6), and a gas passage (211) passing through the positive electrode (22) is provided below the positive electrode (22). A first reaction gas inlet passage (25) and a second reaction gas inlet passage (26) are provided with a partition plate (21); the lower portion of the first reaction gas inlet passage (25) is communicated with the gas passage (211) between the second pair of partition plates (21) on one side close to the carrier drive module (6); the lower portion of the second reaction gas inlet passage (26) is communicated with the gas passage (211) between the negative electrode plate (231) and the positive electrode plate (221); the first reaction gas inlet passage (25) and the second reaction gas inlet passage (26) are respectively connected to a first reaction gas supply device and a second reaction gas supply device; and the positive electrode (22) and the negative electrode (23) are connected to a plasma generator (3).

3. The plasma enhanced spatial atomic layer deposition device according to claim 2, characterized in that: Adjacent pairs of the partition plates (21) enclose an exhaust gap (281), and an exhaust duct (28) passing through all the partition plates (21) is provided between the first reaction gas inlet duct (25) and the positive electrode (22). The lower portion of the exhaust duct (28) is connected to all the exhaust gaps (281), and the exhaust duct (28) is connected to a pipeline with a vacuum baffle valve (8).

4. The plasma enhanced spatial atomic layer deposition device according to claim 3, characterized in that: An inert gas inlet passage (27) passing through all the partition plates (21) is provided between the first reaction gas inlet passage (25) and the exhaust passage (28); the lower portion of the inert gas inlet passage (27) communicates with the gas passage (211) between the first, third and fifth pairs of partition plates (21) on one side close to the carrier drive module (6); and the inert gas inlet passage (27) is connected to an inert gas supply device.

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