CN111952217A

CN111952217A - Substrate processing apparatus

Info

Publication number: CN111952217A
Application number: CN202010396665.4A
Authority: CN
Inventors: 西原一树; 鳅场真树
Original assignee: Screen Holdings Co Ltd
Current assignee: Screen Holdings Co Ltd
Priority date: 2019-05-15
Filing date: 2020-05-12
Publication date: 2020-11-17
Also published as: JP2020188135A; TW202044397A; TWI754913B; JP7373302B2

Abstract

The invention provides a substrate processing apparatus capable of improving uniformity of in-plane etching of a substrate. The substrate processing apparatus (1) is an apparatus for etching the surface of a substrate (W1) by using a gas phase. A substrate processing apparatus (1) is provided with a chamber (10), a heating placement unit (30), a gas introduction unit (40), an exhaust unit (50), and a first heating unit (60). The heating placement unit (30) heats and places a substrate (W1) in the chamber (10). The gas introduction part (40) has an introduction port (41a) provided in the chamber (10) at a position facing the substrate (W1), and introduces an etching gas into the chamber (10) from the introduction port (41 a). The exhaust unit (50) exhausts gas from the chamber (10) through a first exhaust port (12a) formed in the chamber (10). The first heating unit (60) is attached to the chamber (10).

Description

Substrate processing apparatus

Technical Field

The present application relates to a substrate processing apparatus.

Background

Conventionally, as an etching apparatus for etching a substrate, an apparatus for supplying a chemical solution to a substrate has been proposed. When the etching apparatus supplies the chemical solution to the substrate, the chemical solution can act on the substrate to etch the film to be etched. However, if the pattern of the substrate is fine, the chemical solution cannot sufficiently enter the narrow region. As a result, there is a problem that etching becomes insufficient.

Therefore, a vapor phase etching apparatus using no chemical solution has been proposed (for example, patent document 1). The vapor phase etching apparatus etches a substrate using a process gas. The gas phase etching device comprises a chamber and a gas delivery device. A substrate to be etched is placed in the chamber. The gas delivery device supplies a process gas to the substrate from an upper side in the chamber. The process gas acts on the substrate to etch the substrate. Since the process gas is a gas, the process gas can enter a narrow region of the substrate.

In addition, since the gas phase etching apparatus does not use plasma, the manufacturing cost can be reduced.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2014-45125

Disclosure of Invention

Problems to be solved by the invention

In the vapor phase etching apparatus of patent document 1, heating of the substrate is considered. This can facilitate etching of the substrate with a process gas (hereinafter referred to as an etching gas).

However, by heating the substrate, the temperature of the substrate is higher than the temperature of the inner circumferential surface of the chamber. Since the gas is likely to flow to a lower temperature side by convection, the gas near the peripheral edge of the substrate is likely to flow to the inner peripheral surface of the chamber. This reduces the amount of etching at the peripheral edge of the substrate. That is, uniformity of in-plane etching of the substrate is degraded.

Accordingly, an object of the present invention is to provide a substrate processing apparatus capable of improving uniformity of in-plane etching of a substrate.

Means for solving the problems

A first aspect of the substrate processing apparatus is a substrate processing apparatus for etching a surface of a substrate with a gas phase, including: a chamber; a heating placement unit for heating and placing the substrate in the chamber; a gas introduction part having an introduction port provided in the chamber at a position facing the substrate, and introducing an etching gas into the chamber from the introduction port; an exhaust unit configured to externally exhaust gas in the chamber through a first exhaust port formed in the chamber; and a first heating unit attached to the chamber.

A second aspect of the substrate processing apparatus is the substrate processing apparatus according to the first aspect, wherein the first heating unit raises a temperature of an inner peripheral surface of the chamber to a temperature equal to or higher than a temperature of a surface of the substrate.

A third aspect of the substrate processing apparatus is the substrate processing apparatus according to the second aspect, wherein the first heating unit heats the chamber such that a temperature of an inner peripheral surface of the chamber is raised to a value higher by 30 degrees or more than a temperature of a surface of the substrate.

A fourth aspect of the substrate processing apparatus is the substrate processing apparatus according to any one of the first to third aspects, wherein the heating placement unit raises the temperature of the substrate to 50 degrees or more and 200 degrees or less, and the first heating unit raises the temperature of the inner circumferential surface of the chamber to 80 degrees or more and 230 degrees or less.

A fifth aspect of the substrate processing apparatus is the substrate processing apparatus according to any one of the first to fourth aspects, wherein the first heating unit is attached to at least a region of a side wall of the chamber that faces the substrate in a horizontal direction.

A sixth aspect of the substrate processing apparatus is the substrate processing apparatus according to any one of the first to fifth aspects, further comprising: an outer chamber surrounding the chamber; and a second heating unit which is attached to the outer chamber, wherein the first exhaust port of the chamber connects an inner space of the chamber and an outer space between the chamber and the outer chamber to each other, a second exhaust port is formed in the outer chamber, and the exhaust unit exhausts gas in the outer chamber to the outside through the second exhaust port.

A seventh aspect of the substrate processing apparatus is the substrate processing apparatus of the sixth aspect, wherein the second heating unit raises the temperature of the inner circumferential surface of the outer chamber to a temperature equal to or higher than the temperature of the inner circumferential surface of the chamber.

An eighth aspect of the substrate processing apparatus is the substrate processing apparatus according to the sixth or seventh aspect, wherein the second heating unit heats the inner circumferential surface of the outer chamber to a temperature of 100 degrees or higher.

A ninth aspect of the substrate processing apparatus according to any one of the sixth to eighth aspects includes: a first pressure sensor provided in the chamber; a second pressure sensor provided between the chamber and the outer chamber; and a control unit that controls an exhaust gas flow rate of the exhaust unit based on measurement values of the first pressure sensor and the second pressure sensor.

A tenth aspect of the substrate processing apparatus is the substrate processing apparatus of any one of the first to ninth aspects, further comprising a rectifying portion provided between the introduction port and the substrate, for rectifying the etching gas introduced from the introduction port.

An eleventh aspect of the substrate processing apparatus is the substrate processing apparatus of any one of the first to tenth aspects, wherein the first exhaust port is provided in plural, and the plural first exhaust ports are formed at substantially equal intervals in a circumferential direction of the substrate.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the first aspect of the substrate processing apparatus, since the first heating unit can heat the chamber, the temperature of the inner circumferential surface of the chamber can be increased. Therefore, the flow of the etching gas toward the inner peripheral surface of the chamber due to convection can be suppressed. This makes it possible to supply the etching gas to the substrate more uniformly, and further, to improve the uniformity of the in-plane etching of the substrate.

According to the second aspect of the substrate processing apparatus, the flow of the etching gas toward the inner peripheral surface of the chamber due to convection can be further suppressed.

According to the third and fourth aspects of the substrate processing apparatus, since the etching gas easily flows toward the substrate, the etching gas acting on the substrate can be increased. Thus, throughput can be improved.

According to the fifth aspect of the substrate processing apparatus, the region of the inner chamber facing the substrate in the horizontal direction can be efficiently heated. Therefore, the flow of the etching gas formed by convection to the inner peripheral surface of the side wall 22 can be efficiently changed toward the substrate W1.

According to the sixth aspect of the substrate processing apparatus, the possibility that the etching gas liquefies on the inner peripheral surface of the outer chamber can be reduced.

According to the seventh aspect of the substrate processing apparatus, liquefaction of the etching gas can be further suppressed.

According to the eighth aspect of the substrate processing apparatus, liquefaction of the etching gas can be more reliably suppressed.

According to the ninth aspect of the substrate processing apparatus, the pressure in the chamber and the pressure in the outer chamber can be controlled with high accuracy.

According to the tenth aspect of the substrate processing apparatus, since the etching gas is rectified, the uniformity of the in-plane etching of the substrate can be further improved.

According to the eleventh aspect of the substrate processing apparatus, the flow of the gas in the chamber can be made more uniform.

Objects, features, aspects and advantages associated with the technology disclosed in the present specification will become more apparent from the detailed description and the accompanying drawings, which are shown below.

Drawings

Fig. 1 is a diagram schematically showing an example of the structure of a substrate processing apparatus.

Fig. 2 is a diagram schematically showing an example of the structure of the internal chamber.

Fig. 3 is a diagram schematically showing an example of the structure of the rectifying unit.

Fig. 4 is a diagram schematically showing an example of the structure of the substrate processing apparatus.

Fig. 5 is a diagram schematically showing an example of the structure of the substrate processing apparatus.

Fig. 6 is a diagram schematically showing an example of the structure of the substrate processing apparatus.

In the figure:

1. 1A to 1C-a substrate processing apparatus, 10-a chamber (inner chamber), 12 a-a first exhaust port (inner exhaust port), 20-an outer chamber, 23 a-a second exhaust port (outer exhaust port), 30-a heating placement portion, 40-a gas introduction portion, 41A-an introduction port (gas introduction port), 50-an exhaust portion, 60-a first heating portion (heating portion), 61-a second heating portion (heating portion), 80-a rectifying portion, 91-a first pressure sensor (pressure sensor), 92-a second pressure sensor (pressure sensor).

Detailed Description

Hereinafter, embodiments will be described with reference to the drawings. In the drawings, the same reference numerals are given to portions having the same structure and function, and redundant description is omitted in the following description. The following embodiments are merely examples, and do not limit the technical scope. In the drawings, the size and number of the respective portions may be exaggerated or simplified for easy understanding.

First embodiment

Structure of substrate processing apparatus

Fig. 1 is a diagram schematically showing an example of the structure of a substrate processing apparatus 1. The substrate processing apparatus 1 is a vapor phase etching apparatus for etching the surface of the substrate W1 with a vapor phase. Since the substrate processing apparatus 1 performs the etching process on the substrate W1 without using plasma, damage to the substrate W1 due to plasma can be avoided. Further, since a mechanism for generating plasma is not required, the manufacturing cost of the substrate processing apparatus 1 can be reduced.

As illustrated in fig. 1, the substrate processing apparatus 1 includes an inner chamber (chamber) 10, an outer chamber 20, a heating placement unit 30, a gas introduction unit 40, an exhaust unit 50, a heating unit 60, and a control unit 70.

The inner chamber 10 is a closed box forming a processing space V1. The inner chamber 10 is formed of, for example, metal. As illustrated in fig. 1, the inner chamber 10 has an upper plate 11, a side wall 12, and a lower plate 13. The upper plate 11 and the lower plate 13 face each other with a gap therebetween in the vertical direction. The side wall 12 connects the periphery of the upper plate 11 and the periphery of the lower plate 13. The side wall 12 is, for example, substantially cylindrical in shape. In this case, the upper plate 11 and the lower plate 13 are substantially circular in a plan view (i.e., when viewed in the vertical direction). The internal space of the inner chamber 10 enclosed by the upper plate 11, the side wall 12, and the lower plate 13 corresponds to the processing space V1.

The outer chamber 20 is a closed box body surrounding the outside of the inner chamber 10. The outer chamber 20 is formed of, for example, metal. As illustrated in fig. 1, the outer chamber 20 has an upper plate 21, a side wall 22, and a lower plate 23. The lower plate 23 has an annular shape, and the inner peripheral edge thereof is connected to the outer peripheral edge of the lower plate 13 of the inner chamber 10. The lower plate 13 and the lower plate 23 may be formed integrally. The upper plate 21 of the outer chamber 20 is located above the upper plate 11 of the inner chamber 10, and faces the upper plate 11 with a gap. The upper plate 21 of the outer chamber 20 extends outward beyond the periphery of the upper plate 11 of the inner chamber 10 in plan view.

The side wall 22 of the outer chamber 20 connects the peripheral edge of the upper plate 21 and the outer peripheral edge of the lower plate 23 to surround the side wall 12 of the inner chamber 10 from the outside. The sidewall 22 of the outer chamber 20 has, for example, a substantially cylindrical shape concentric with the sidewall 12 of the inner chamber 10. In this case, the upper plate 21 of the outer chamber 20 is substantially circular in plan view concentric with the upper plate 11 of the inner chamber 10, and the lower plate 23 of the outer chamber 20 has a substantially annular shape concentric with the lower plate 13 of the inner chamber 10.

As described above, in the example of fig. 1, the substrate processing apparatus 1 has a dual structure of the inner chamber 10 and the outer chamber 20. Hereinafter, the space between the inner chamber 10 and the outer chamber 20 is also referred to as an outer space V2.

An inner exhaust port 12a is formed in the inner chamber 10. In the example of fig. 1, the inner exhaust port 12a is formed in the sidewall 12 of the inner chamber 10. The inner exhaust port 12a penetrates the sidewall 12 in the thickness direction of the sidewall 12, and connects the processing space V1 in the inner chamber 10 and the outer space V2 between the inner chamber 10 and the outer chamber 20 to each other. In the example of fig. 1, the inner exhaust port 12a is formed in a lower portion of the side wall 12. The gas in the processing space V1 is discharged to the outer space V2 through the inner exhaust port 12 a.

The inner exhaust port 12a may be provided in plurality. Fig. 2 is a diagram schematically showing an example of the structure of the internal chamber 10. A horizontal cross-sectional view of the inner chamber 10 is shown in fig. 2. In the example of fig. 2, four inner exhaust ports 12a are formed in the inner chamber 10. Four inner exhaust ports 12a are formed at substantially equal intervals in the circumferential direction of the side wall 12. Accordingly, the gas in the processing space V1 is more uniformly discharged in a plan view. This makes it possible to make the flow of the gas flowing through the processing space V1 more uniform. The number of the inner exhaust ports 12a can be changed as appropriate, and is more preferably three or more. If the number of the inner exhaust ports 12a is three or more, the flow of the gas can be more appropriately made uniform.

Referring again to fig. 1, an outer exhaust port 23a is formed in the outer chamber 20. The exhaust portion 50 sucks the gas in the outer space V2 between the inner chamber 10 and the outer chamber 20 through the outer exhaust ports 23a and exhausts the gas to the outside. Thereby, the gas in the processing space V1 is also discharged to the exhaust unit 50 through the inner exhaust port 12a and the outer exhaust port 23 a. Therefore, the pressure in the outer chamber 20 (the processing space V1 and the outer space V2) is reduced.

In the example of fig. 1, the outer exhaust port 23a is formed in the lower plate 23 of the outer chamber 20, and penetrates the lower plate 23 in the thickness direction of the lower plate 23. In the example of fig. 1, a plurality of (two in this case) outer exhaust ports 23a are formed. The plurality of outer exhaust ports 23a may also be formed substantially equally spaced in the circumferential direction. Thereby, the gas in the processing space V1 is more uniformly discharged from the inner exhaust port 12 a.

In the example of fig. 1, the exhaust unit 50 includes an exhaust pipe 51, an exhaust valve 52, and a vacuum pump 53. The exhaust pipe 51 is connected to the outer exhaust port 23a of the outer chamber 20. In the example of fig. 1, since a plurality of outer exhaust ports 23a are formed, a plurality of exhaust pipes 51 are provided. In the example of fig. 1, the exhaust pipes 51 are joined together and connected to a vacuum pump 53.

The vacuum pump 53 sucks the gas in the exhaust pipe 51 and discharges the gas to the outside. The vacuum pump 53 is controlled by the control unit 70. The exhaust valve 52 is provided in the middle of the exhaust pipe 51, and adjusts the opening degree of the flow path in the exhaust pipe 51. The opening degree of the exhaust valve 52 is controlled by the control unit 70. The control unit 70 controls the exhaust valve 52 and the vacuum pump 53 so that the pressure in the processing space V1 becomes a predetermined processing pressure, for example.

A carrying-in/out port (not shown) for carrying in/out the substrate W1 is formed in the inner chamber 10 and the outer chamber 20. For example, a carrying-in/out port is formed in each of the side wall 12 of the inner chamber 10 and the side wall 22 of the outer chamber 20. A gate (not shown) is provided at each of the carry-in/out ports. By closing the shutter, the carry-in/out port can be hermetically closed, and by opening the shutter, the carry-in/out port can be opened. The opening and closing of the shutter is controlled by the control unit 70.

The heating carrier 30 is provided in the internal chamber 10, and heats and places the substrate W1. The heating carrier 30 includes a mounting table 31 and a heating unit 32. A substrate W1 is placed on the mounting table 31. The substrate W1 is placed on the mounting table 31 in a substantially horizontal posture. In other words, the substrate W1 is placed on the mounting table 31 in a posture in which the thickness direction thereof is in the vertical direction.

The substrate W1 is, for example, a semiconductor substrate. When the substrate W1 is a semiconductor substrate, the substrate W1 has a substantially disk shape. In a step before the substrate processing apparatus 1 is carried in, a film to be etched is formed on the upper surface of the substrate W1. The film to be etched is not particularly limited, but is, for example, an oxide film or a nitride film. Here, as an example, an oxide film is formed on the upper surface of the substrate W1 by CVD (chemical vapor deposition), ALD (atomic layer volume method), thermal oxidation, or the like.

The mounting table 31 may be provided with a chuck mechanism for holding the substrate W1. For example, the mounting table 31 may have an upper surface facing the lower surface of the substrate W1, and a plurality of chuck pins (not shown) may be provided on the upper surface. The plurality of chuck pins are provided substantially at equal intervals along the peripheral edge of the substrate W1, and hold the peripheral edge of the substrate W1. As the chuck mechanism, various mechanisms other than the chuck pins (for example, a suction chuck and the like) can be used. Here, the mounting table 31 includes a chuck mechanism, for example. The chuck mechanism of the mounting table 31 is controlled by the control unit 70.

The heating unit 32 heats the substrate W1 placed on the mounting table 31. The heating unit 32 is provided below the substrate W1, and includes, for example, a resistance wire that generates joule heat. The resistance wire is suitably covered with an insulating film. As a more specific example, the heating unit 32 may be built in the mounting table 31. For example, the resistance wire is two-dimensionally arranged in a plan view. The mounting table 31 is heated by a built-in heating unit 32. Heating unit 32 is controlled by control unit 70.

In the example of fig. 1, the heating placement unit 30 includes a rotation mechanism 33. The rotation mechanism 33 rotates the substrate W1 around a rotation axis passing through the center of the substrate W1 and extending in the vertical direction. For example, the rotation mechanism 33 includes a motor (not shown) and a shaft (not shown). One end of the shaft is connected to the lower surface of the mounting table 31, and the other end is connected to the motor. The shaft transmits the rotational force of the motor to the table 31 to rotate the table 31 about the rotational axis. This enables the substrate W1 held on the mounting table 31 to be rotated. The rotation mechanism 33 is controlled by the control unit 70.

The gas introducing unit 40 has a gas inlet 41a provided in the inner chamber 10, and introduces an etching gas into the processing space V1 from the gas inlet 41 a. The gas introduction port 41a is provided at a position facing the surface (upper surface in fig. 1) of the substrate W1. In the example of fig. 1, the gas introduction port 41a is located above the substrate W1 held on the mounting table 31. The gas introduction portion 40 discharges the etching gas from the gas introduction port 41a toward the upper surface of the substrate W1. In the example of fig. 1, the direction of the flow of the etching gas in the process space V1 is schematically shown by a dashed arrow.

The etching gas acts on the upper surface of the substrate W1 to etch the film to be etched on the upper surface. The etching gas includes a reactive gas such as hydrofluoric acid gas or fluorine gas. The etching gas may further include an additive gas having a hydroxyl group (OH group) such as water vapor or ethanol gas. The etching gas may further include an inert gas such as argon, helium, or nitrogen. The inert gas mentioned here is a gas having a low reactivity with the substrate W1.

In the example of fig. 1, the gas introducing portion 40 includes an introducing pipe 41, an introducing valve 42, and a gas supply source 43. The introduction pipe 41 penetrates the inner chamber 10 and the outer chamber 20, and has one end located above the substrate W1 in the processing space V1 in the inner chamber 10. A gas inlet 41a is formed at one end of the inlet pipe 41. In the example of fig. 1, the introduction pipe 41 extends in the vertical direction in the outer chamber 20, and penetrates the upper plate 11 of the inner chamber 10 and the upper plate 21 of the outer chamber 20 in the thickness direction thereof. The inlet pipe 41 and the inner chamber 10 are hermetically sealed by a predetermined sealing portion (e.g., an O-ring), and the inlet pipe 41 and the outer chamber 20 are also hermetically sealed by a predetermined sealing portion (e.g., an O-ring).

The other end of the introduction pipe 41 is connected to a gas supply source 43. The gas supply source 43 supplies an etching gas to the introduction pipe 41. In the example of fig. 1, only one gas supply source 43 is shown in a simple manner, but as described above, the etching gas can include a plurality of gases, and therefore a plurality of gas supply sources 43 corresponding to the plurality of gases can be provided. In this case, the introduction pipe 41 is branched into a plurality of branches, and the branch ends thereof are connected to the gas supply sources 43, respectively.

The introduction valve 42 is provided in the middle of the introduction pipe 41. When a plurality of gas supply sources 43 are provided and the introduction pipe 41 is branched into a plurality of branches, the branch pipes are provided with introduction valves 42, respectively. The introduction valve 42 is controlled by the control unit 70. The introduction valve 42 may be a valve capable of adjusting the flow rate of the gas flowing through the inside of the introduction pipe 41.

By opening the introduction valve 42, the etching gas flows from the gas supply source 43 through the inside of the introduction pipe 41, and is ejected from the gas introduction port 41 a. The etching gas introduced into the processing space V1 from the gas inlet 41a flows downward. In the example of fig. 1, a rectifying unit 80 described below is provided, and the etching gas is rectified by passing through the rectifying unit 80. The etching gas having passed through the rectifying unit 80 flows over the upper surface of the substrate W1, and the film to be etched on the upper surface is subjected to vapor phase decomposition and is etched.

Since the inner exhaust port 12a is located below the substrate W1 on the mounting table 31, the gas generated by the vapor phase decomposition flows downward from the peripheral edge of the substrate W1 and is exhausted to the exhaust portion 50 through the inner exhaust port 12a and the outer exhaust port 23 a. Further, the etching gas which is not favorable for etching is also discharged to the exhaust portion 50 through the inner exhaust port 12a and the outer exhaust port 23 a.

The rectifying portion 80 is provided between the gas introduction port 41a of the gas introduction portion 40 and the heating placement portion 30. The rectifying portion 80 has air permeability, and the etching gas introduced into the processing space V1 from the gas introduction portion 40 passes through the rectifying portion 80, whereby the etching gas is rectified. The etching gas having passed through the rectifying portion 80 flows further downward and is supplied onto the upper surface of the substrate W1. The distance between the rectifying portion 80 and the substrate W1 is set to, for example, about 10[ mm ] or less. When the distance between the rectifying unit 80 and the substrate W1 is long, the etching gas rectified by the rectifying unit 80 may be disturbed again in the vicinity of the upper surface of the substrate W1, but if the distance is about 10[ mm ] or less, such disturbance is less likely to occur.

Fig. 3 is a plan view schematically showing an example of the structure of the rectifying unit 80. In the example of fig. 3, the rectifying portion 80 is a punched plate. The rectifying portion 80 has a plate-like shape and is provided in an attitude in which the thickness direction thereof is in the vertical direction. The rectifying portion 80 is substantially circular in plan view, and its peripheral edge is fixed to the inner peripheral surface of the side wall 22 of the inner chamber 10. In the example of fig. 3, a plurality of through holes 80a are formed in the rectifying portion 80. Each through hole 80a is, for example, substantially circular in plan view, and its diameter is set to, for example, about 0.1 to 2[ mm ]. The through holes 80a are two-dimensionally distributed in a plan view, and in the example of fig. 3, are arranged substantially in a matrix. The size and number of the plurality of through holes 80a can be changed as appropriate.

In the example of fig. 1, one rectifying unit 80 is provided, but a plurality of rectifying units 80 may be provided. The plurality of flow regulating portions 80 are provided at intervals in the vertical direction between the gas introduction port 41a and the substrate W1. The through-holes 80a may be shifted in position between the vertically adjacent rectifying portions 80. For example, the first rectifying unit 80 and the second rectifying unit 80 are provided in the following manner. The through-hole 80a of the first rectifying portion 80 does not face the through-hole 80a of the second rectifying portion 80 in the vertical direction, but faces a region where the through-hole 80a is not formed. In contrast, the through-hole 80a of the second rectifying portion 80 also faces the region of the first rectifying portion 80 where the through-hole 80a is not provided. Accordingly, the gas is further rectified by passing through the plurality of rectifying portions 80.

The rectifying portion 80 may have a mesh shape. For example, the rectifying portion 80 may have a mesh structure coated with a fluorine resin such as PTFE (polytetrafluoroethylene).

The heating unit 60 is attached to the inner chamber 10 and heats the inner chamber 10. The heating unit 60 is controlled by the control unit 70 to raise the temperature of the inner circumferential surface of the inner chamber 10 to a temperature equal to or higher than the temperature of the substrate W1 held on the stage 31.

As illustrated in fig. 1, the heating unit 60 may be provided on the outer peripheral surface of the inner chamber 10. In the example of fig. 1, the heating unit 60 is provided on the outer peripheral surface of the side wall 12 of the inner chamber 10. The heating unit 60 may have a cylindrical shape surrounding the side wall 12. The heating unit 60 may be in close contact with the outer circumferential surface of the inner chamber 10. Accordingly, the heating unit 60 can heat the inner chamber 10 more efficiently. The heating unit 60 is provided in a region of the side wall 12 including at least a position horizontally opposed to the substrate W1.

The heating unit 60 may have a resistance wire (not shown) that generates joule heat, for example. The resistance wire is suitably covered with an insulating film. The inner chamber 10 may be heated by arranging the resistance wire along the outer peripheral surface of the inner chamber 10. The heating unit 60 may include a heat conductive member (e.g., metal) that has a resistance wire built therein and is in close contact with the outer peripheral surface of the inner chamber 10.

Alternatively, the heating unit 60 may include a heat medium pipe (not shown). The heat medium pipe is arranged along the outer peripheral surface of the side wall 12 of the inner chamber 10. For example, the heat medium pipe is spirally arranged to surround the side wall 12. A high-temperature heat medium (also referred to as a refrigerant) flows through the heat medium pipe. The inner chamber 10 can be heated by heat exchange between the heat medium and the inner chamber 10. Both ends of the heat medium pipe are connected to a heating unit (not shown). When the heat medium that has radiated heat into the inner chamber 10 and has become a low temperature flows from one end of the heat medium pipe into the heating portion, the heating portion heats the heat medium and supplies a high-temperature heat medium to the other end of the heat medium pipe. Thereby, the high-temperature heat medium flows through the heat medium pipe again to heat the inner chamber 10. As described above, the heat medium circulates in the heat medium pipe. The heating unit 60 may include a heat-conductive member (e.g., metal) that incorporates a heat medium pipe and is in close contact with the outer peripheral surface of the inner chamber 10.

The heating unit 60 is not necessarily provided on the outer peripheral surface of the inner chamber 10. For example, the heating unit 60 may be embedded in the inner chamber 10 itself, or may be provided on the inner circumferential surface of the inner chamber 10. In the case where the heating portion 60 is provided on the outer peripheral surface of the inner chamber 10, the heating portion 60 is easier to install than the case where the heating portion 60 is embedded in the inner chamber 10. Further, since the heating unit 60 is not exposed to the processing space V1 in the inner chamber 10, even if particles or the like are generated by the heating unit 60 itself, the particles are less likely to adhere to the substrate W1.

The control unit 70 controls the substrate processing apparatus 1 collectively. The control unit 70 is constituted by, for example, a general fa (factory automation) computer in which a cpu (central Processing unit) that performs various kinds of arithmetic Processing, a rom (read only memory) that stores programs and the like, a ram (random Access memory) that becomes a work Area for arithmetic Processing, a hard disk that stores programs, various data files and the like, a data communication unit having a data communication function via a lan (local Area network) and the like are connected to each other via a bus and the like. The control unit 70 is connected to an input unit or the like including a display for performing various displays, a keyboard, a mouse, and the like. A part or all of the functions executed by the control unit 70 may be realized by a dedicated hardware circuit.

Outline of operation of substrate processing apparatus

First, the controller 70 controls the shutter of the inner chamber 10 and the shutter of the outer chamber 20 to open both the shutters. This opens the carry-in/out port of the substrate processing apparatus 1. The substrate transport apparatus, not shown, carries the substrate W1 into the substrate processing apparatus 1 through the carry-out/carry-in port, and places the substrate W on the heating carrier 30. When the carrying-in operation by the substrate transport apparatus is completed, the control unit 70 controls the two gates to close the two gates.

The controller 70 controls the exhaust unit 50 to reduce the pressure in the processing space V1 in the inner chamber 10 to a predetermined processing pressure. The predetermined processing pressure is set to be, for example, about 1 to 300[ Torr ]. The control section 70 may control the exhaust section 50 so as to maintain the pressure of the process space V1 within a predetermined pressure range during the etching process.

The controller 70 controls the heating unit 32 and the heating unit 60 to heat the substrate W1 and the internal chamber 10, respectively. The heating unit 32 heats the substrate W1 to raise the temperature of the upper surface of the substrate W1 to a temperature in a range of, for example, 50 degrees or more and 200 degrees or less.

The heating unit 60 heats the inner chamber 10 so that the temperature of the inner circumferential surface of the inner chamber 10 becomes equal to or higher than the temperature of the upper surface of the substrate W1. More specifically, the heating unit 60 heats the inner chamber 10 so that the temperature of at least a region of the inner circumferential surface of the sidewall 12, which horizontally faces the substrate W1, becomes equal to or higher than the temperature of the upper surface of the substrate W1. The temperature of the inner circumferential surface of the inner chamber 10 is set to a temperature in a range of, for example, 80 degrees or more and 230 degrees or less, and is set to a temperature higher by, for example, 30 degrees or more than the temperature of the upper surface of the substrate W1.

In the etching process, the controller 70 may control the

heating units

32 and 60 so as to maintain the temperatures of the substrate W1 and the internal chamber 10 within respective temperature ranges.

Next, the controller 70 controls the rotation mechanism 33 to rotate the substrate W1. In the etching process, the controller 70 controls the rotating mechanism 33 so as to maintain the rotation speed of the substrate W1 within a predetermined speed range.

Next, the controller 70 controls the gas introducing unit 40 to introduce the etching gas into the processing space V1 in the inner chamber 10. For example, the flow rate of the reactive gas is set to about 100 to 3000[ sccm ], the flow rate of the inert gas is set to about 100 to 15000[ sccm ], and the flow rate of the additive gas is set to 0 to 3000[ sccm ].

The etching gas discharged from the gas inlet 41a is rectified by the rectifying unit 80, and the rectified etching gas decomposes the film to be etched on the upper surface of the substrate W1 in a vapor phase and etches the film. The gas generated by the vapor phase decomposition and the etching gas not contributing to the vapor phase decomposition are discharged to the exhaust portion 50 through the inner exhaust port 12a and the outer exhaust port 23 a.

When a process period required for the etching process has elapsed from the start of the introduction of the etching gas, the control unit 70 controls various components of the substrate processing apparatus 1 to stop the operations. This completes the etching process performed on the substrate W1.

As described above, the substrate processing apparatus 1 is provided with the heating unit 60, and the heating unit 60 heats the inner chamber 10 during the etching process. Here, for comparison, a case where the heating portion 60 is not provided will be described. In this case, the temperature of the upper surface of the substrate W1 is higher than the temperature of the inner circumferential surface of the side wall 12 of the inner chamber 10. Therefore, the etching gas flowing downward from the upper side of the substrate W1 toward the peripheral edge portion of the upper surface of the substrate W1 is likely to flow toward the inner peripheral surface of the side wall 12 of the inner chamber 10 by convection. Accordingly, the etching gas flowing toward the peripheral edge portion of the upper surface of the substrate W1 is reduced.

Further, the lower the temperature of the member, the more easily the etching gas adsorbs to the member, and when the temperature of the inner circumferential surface of the inner chamber 10 is low, the adsorption amount of the etching gas on the inner circumferential surface of the inner chamber 10 increases. This also reduces the flow of the etching gas toward the peripheral edge portion of the upper surface of the substrate W1.

As described above, when the etching gas flowing toward the peripheral edge of the upper surface of the substrate W1 decreases, the difference between the etching amount at the center portion and the etching amount at the peripheral edge portion of the upper surface of the substrate W1 increases. That is, the uniformity of in-plane etching of the substrate W1 is reduced.

In contrast, the heating unit 60 raises the temperature of the inner peripheral surface of the internal chamber 10 to a temperature equal to or higher than the temperature of the upper surface of the substrate W1. Therefore, the flow of the etching gas toward the inner circumferential surface of the inner chamber 10 by convection can be suppressed. Further, the amount of etching gas adsorbed on the inner circumferential surface of the inner chamber 10 can be reduced.

Accordingly, the etching gas is also supplied to the peripheral edge portion of the upper surface of the substrate W1 appropriately, and acts more uniformly on the upper surface of the substrate W1. Therefore, the uniformity of in-plane etching of the substrate W1 can be improved.

When the temperature of the inner circumferential surface of the side wall 12 of the inner chamber 10 is higher than the temperature of the upper surface of the substrate W1, the etching gas flowing downward on the outer circumferential side of the substrate W1 easily flows toward the upper surface of the substrate W1. This can increase the amount of etching gas acting on the upper surface of the substrate W1. Thus, throughput can be improved.

Further, since the inner peripheral surface of the inner chamber 10 has a high temperature, the etching gas is less likely to be adsorbed on the inner peripheral surface of the inner chamber 10 and liquefied. This reduces the possibility of corrosion of the inner chamber 10 due to liquefaction of the etching gas. For example, when water vapor is used as the additive gas, if the pressure of the processing space V1 is about 100 Torr, the water vapor liquefies at a temperature of about 50 degrees. If liquid water adheres to the inner chamber 10, for example, the inner chamber 10 may corrode. The heating unit 60 heats the inner chamber 10 to raise the temperature of the inner circumferential surface of the inner chamber 10 to a temperature higher than 50 degrees, thereby suppressing or avoiding such corrosion. The reactive gas liquefies at a temperature of, for example, about 20 ℃. By heating the inner chamber 10 by the heating unit 60, liquefaction of the reactive gas can be more reliably suppressed.

However, if the temperature of the inner peripheral surface of the inner chamber 10 is too high, the peripheral edge of the substrate W1 is heated by radiant heat from the side wall 12 of the inner chamber 10. Thus, the temperature of the peripheral portion of the upper surface of the substrate W1 may be higher than the temperature of the central portion of the substrate W1. Such a difference in the temperature of the substrate W1 is undesirable from the viewpoint of uniformity of in-plane etching. Therefore, it is desirable to control the temperature of the inner peripheral surface of the inner chamber 10 so that the temperature difference of the substrate W1 is within a predetermined range.

In the above example, the heating unit 60 is attached to at least a region of the side wall 12 of the inner chamber 10 that horizontally faces the substrate W1. Accordingly, the heating portion 60 can efficiently heat the region in the side wall 12. Therefore, the flow of the etching gas formed by convection to the inner peripheral surface of the side wall 22 can be efficiently changed toward the substrate W1.

In the above example, the rotation mechanism 33 rotates the substrate W1 during the etching process. Thus, the etching gas acts more uniformly on the upper surface of the substrate W1. Therefore, the uniformity of in-plane etching can be further improved.

In the above example, the substrate processing apparatus 1 includes the rectifying unit 80, but the rectifying unit 80 may not be provided. This is because: the uniformity of the in-plane etching of the substrate W1 can be improved by heating the inner chamber 10 by the heating unit 60. Naturally, in order to further improve the uniformity of in-plane etching, it is desirable to provide the rectifying portion 80. Similarly, the rotation mechanism 33 is not necessarily provided, but the rotation mechanism 33 is desirably provided in order to further improve the uniformity of in-plane etching.

In the above example, the heating unit 60 is provided on the side wall 12 of the inner chamber 10, but is not limited thereto. The heating unit 60 may be provided in the upper plate 11 or the lower plate 13. In short, the heating unit 60 may be provided on at least one of the upper plate 11, the side wall 12, and the lower plate 13, and may be configured to raise the temperature of the inner circumferential surface of the inner chamber 10 (at least a region horizontally opposed to the substrate W1) to a temperature equal to or higher than the temperature of the upper surface of the substrate W1.

Second embodiment

Fig. 4 is a diagram schematically showing an example of the structure of the substrate processing apparatus 1A. The substrate processing apparatus 1A has the same configuration as the substrate processing apparatus 1 except for the presence or absence of the heating portion 61. The heating unit 61 is attached to the outer chamber 20 and heats the outer chamber 20. An example of the configuration of the heating unit 61 is the same as that of the heating unit 60. The heating section 61 is controlled by the control section 70.

As illustrated in fig. 4, the heating portion 61 may be provided on the outer peripheral surface of the outer chamber 20. For example, the heating portion 61 has a cylindrical shape that circumferentially surrounds the outer peripheral surface of the side wall 22 of the outer chamber 20. The heating part 61 may be closely attached to the outer circumferential surface of the outer chamber 20. This enables the heating unit 61 to heat the outer chamber 20 more efficiently.

The heating unit 61 heats the outer chamber 20 so that the temperature of the inner circumferential surface of the outer chamber 20 is maintained within a predetermined temperature range during the etching process. As the predetermined temperature range, a temperature range capable of suppressing liquefaction of the etching gas is adopted. Specifically, a temperature range higher than the boiling point of the etching gas (the boiling point in the process pressure) is used. This can reduce the possibility of the etching gas liquefying on the inner peripheral surface of the outer chamber 20. As a specific example, the heating unit 61 may heat the inner circumferential surface of the outer chamber 20 to 100 degrees or more. Accordingly, for example, even if water vapor is contained as the additive gas, liquefaction of the water vapor on the inner peripheral surface of the outer chamber 20 can be avoided.

In the substrate processing apparatus 1A, since the inner chamber 10 is provided on the inner peripheral side of the outer chamber 20, even if the temperature of the outer chamber 20 is high, the radiant heat from the outer chamber 20 is blocked by the inner chamber 10 and does not directly irradiate the substrate W1. Therefore, even if the temperature of the inner peripheral surface of the outer chamber 20 is high, the radiant heat generated by the outer chamber 20 hardly affects the temperature distribution of the substrate W1. In other words, the temperature of the inner peripheral surface of the outer chamber 20 is less likely to affect the temperature distribution of the substrate W1 than the inner chamber 10. Therefore, even if the temperature of the inner peripheral surface of the outer chamber 20 is high, the uniformity of the in-plane etching of the substrate W1 is less likely to decrease.

Therefore, the heating unit 61 may heat the outer chamber 20 to raise the temperature of the inner circumferential surface of the outer chamber 20 to a temperature equal to or higher than the temperature of the inner circumferential surface of the inner chamber 10. Accordingly, the possibility of the etching gas liquefying on the inner circumferential surface of the outer chamber 20 can be reduced more than in the case where the temperature of the inner circumferential surface of the outer chamber 20 is lower than the temperature of the inner circumferential surface of the inner chamber 10. This can further reduce the possibility of corrosion of the outer chamber 20.

In the above example, the heating unit 61 is attached to the side wall 22 of the outer chamber 20, but may be provided on at least one of the upper plate 21, the side wall 22, and the lower plate 23. In the above example, the heating unit 61 is attached to the outer peripheral surface of the outer chamber 20, but may be embedded in the outer chamber 20 or attached to the inner peripheral surface of the outer chamber 20.

Third embodiment

Fig. 5 is a diagram schematically showing an example of the structure of the substrate processing apparatus 1B. The substrate processing apparatus 1B has the same configuration as the substrate processing apparatus 1A except for the presence or absence of the rectifying unit 81.

The rectifying unit 81 is provided in the inner chamber 10 and is located downstream of the substrate W1 in the flow of the etching gas in the processing space V1. More specifically, the rectifying portion 81 is provided so that the upper surface of the rectifying portion 81 is the same as the upper surface of the substrate W1 or is at a height position lower than the upper surface. The rectifying portion 81 has a substantially annular plate-like shape, and the thickness direction thereof is set to be in the vertical direction. As illustrated in fig. 5, the rectifying unit 81 is provided so as to surround the substrate W1 or the heating placement unit 30. The outer peripheral edge of the rectifying portion 81 may be fixed to the inner peripheral surface of the inner chamber 10.

The rectifying portion 81 has air permeability and rectifies the etching gas. Specifically, the rectifying portion 81 is formed with a plurality of through holes (not shown) penetrating the rectifying portion 81 in the thickness direction. The through holes formed in the rectifying portion 81 have the same size as the through holes 80a formed in the rectifying portion 80, and are arranged so as to be dispersed in a plan view, similarly to the through holes 80 a. Like the rectifying portion 80, the rectifying portion 81 may be a punched plate or may have a mesh structure.

The rectifying unit 81 can rectify the flow of the etching gas at a position downstream of the substrate W1. Since the etching gas continuously flows in the processing space V1, the flow of the etching gas on the downstream side can be rectified to also rectify the flow of the etching gas on the upper side of the substrate W1. This can further improve the uniformity of in-plane etching of the substrate W1.

As with the rectifying unit 80, a plurality of rectifying units 81 may be provided. The plurality of flow regulating portions 81 are provided at intervals in the vertical direction on the downstream side of the substrate W1. The through holes of the adjacent rectifying portions 81 are formed to be offset from each other in a plan view. Accordingly, the flow of the gas can be further rectified at a position downstream of the substrate W1.

In the above example, the rectifying unit 81 is provided in the substrate processing apparatus 1A, but the rectifying unit 81 may be provided in the substrate processing apparatus 1.

Fourth embodiment

Fig. 6 is a diagram schematically showing an example of the structure of the substrate processing apparatus 1C. The substrate processing apparatus 1C has the same configuration as the substrate processing apparatus 1B except for the presence or absence of the pressure sensor 91 and the pressure sensor 92.

The pressure sensor 91 is provided in the inner chamber 10. The pressure sensor 91 measures the pressure in the processing space V1, and outputs the measured value to the control unit 70. The position of the pressure sensor 91 in the processing space V1 is not particularly limited, but in the example of fig. 6, the pressure sensor 91 is provided at a height position between the rectifying unit 80 and the substrate W1. The pressure sensor 91 is located outside the substrate W1 in plan view.

The pressure sensor 92 is provided in the outside space V2 between the inner chamber 10 and the outer chamber 20. The pressure sensor 92 measures the pressure in the outer space V2, and outputs the measured value to the control unit 70. The position of the pressure sensor 92 in the outside space V2 is also not particularly limited.

The controller 70 controls the exhaust flow rate of the gas in the exhaust unit 50 so that the pressure in the processing space V1 and the pressure in the outer space V2 are within predetermined pressure ranges, based on the measurement values input from the pressure sensor 91 and the pressure sensor 92.

Accordingly, the pressure of the processing space V1 in the inner chamber 10 and the pressure of the outer space V2 between the inner chamber 10 and the outer chamber 20 can be controlled with high accuracy.

Further, since the etching gas is introduced from the gas introduction portion 40 into the process space V1, the pressure of the process space V1 can be made higher than the pressure of the outer space V2. Therefore, inflow of the gas from the outer space V2 to the processing space V1 can be suppressed. Therefore, the possibility of foreign matter such as particles being mixed into the processing space V1 can be reduced.

In the above example, the pressure sensor 91 and the pressure sensor 92 are provided in the substrate processing apparatus 1B, but the pressure sensor 91 and the pressure sensor 92 may be provided in the substrate processing apparatus 1 or the substrate processing apparatus 1A.

While the embodiments have been described above, the substrate processing apparatus 1 may be variously modified without departing from the scope of the embodiments. In the present embodiment, it is possible to freely combine the respective embodiments, to modify any of the components of the respective embodiments, or to omit any of the components of the respective embodiments within the scope of the disclosure.

Claims

1. A substrate processing apparatus for etching a surface of a substrate with a gas phase, comprising:

a chamber;

a heating placement unit for heating and placing the substrate in the chamber;

a gas introduction part having an introduction port provided in the chamber at a position facing the substrate, and introducing an etching gas into the chamber from the introduction port;

an exhaust unit configured to externally exhaust gas in the chamber through a first exhaust port formed in the chamber; and

and a first heating unit mounted in the chamber.

2. The substrate processing apparatus according to claim 1,

the first heating unit raises the temperature of the inner circumferential surface of the chamber to a temperature equal to or higher than the temperature of the surface of the substrate.

3. The substrate processing apparatus according to claim 2,

the first heating unit heats the chamber so that a temperature of an inner circumferential surface of the chamber is raised to a value higher by 30 degrees or more than a temperature of a surface of the substrate.

4. The substrate processing apparatus according to any one of claims 1 to 3,

the heating carrier part heats the temperature of the substrate to 50-200 degrees,

the first heating unit heats the inner circumferential surface of the chamber to 80 to 230 degrees.

5. The substrate processing apparatus according to any one of claims 1 to 3,

the first heating unit is attached to a region of a side wall of the chamber that faces the substrate at least in a horizontal direction.

6. The substrate processing apparatus according to any one of claims 1 to 3, further comprising:

an outer chamber surrounding the chamber; and

a second heating part installed in the outer chamber,

the first exhaust port of the chamber connects an inner space of the chamber and an outer space between the chamber and the outer chamber to each other,

a second exhaust port is formed in the outer chamber,

the exhaust unit exhausts the gas in the outer chamber to the outside through the second exhaust port.

7. The substrate processing apparatus according to claim 6,

the second heating unit heats the inner circumferential surface of the outer chamber to a temperature equal to or higher than the temperature of the inner circumferential surface of the chamber.

8. The substrate processing apparatus according to claim 6,

the second heating unit heats the inner circumferential surface of the outer chamber to 100 degrees or higher.

9. The substrate processing apparatus according to claim 6, comprising:

a first pressure sensor provided in the chamber;

a second pressure sensor provided between the chamber and the outer chamber; and

and a control unit that controls the flow rate of the exhaust gas of the exhaust unit based on the measurement values of the first pressure sensor and the second pressure sensor.

10. The substrate processing apparatus according to any one of claims 1 to 3,

the etching apparatus further includes a rectifying unit provided between the inlet and the substrate and rectifying the etching gas introduced from the inlet.

11. The substrate processing apparatus according to any one of claims 1 to 3,

the first exhaust port is provided in plurality,

the plurality of first exhaust ports are formed at substantially equal intervals in the circumferential direction of the substrate.