JP2013187449A - Etching device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an etching device in which ammonium fluorosilicate on a substrate can be removed by a simple configuration.SOLUTION: The etching device includes an etching section for etching a silicon oxide film on a substrate at 100°C or less, by using NHgas and HF gas in a chamber. The etching section includes a gas supply section disposed at a position facing a substrate support base and supplying the NHgas and HF gas to the substrate support base side, a window of transparent member disposed, as a part of the wall surface of the chamber, at a position closer to the outer peripheral side than the gas supply section in the chamber, and a heating section disposed near the window and heating inside the chamber. The heating section sublimates ammonium fluorosilicate adhering onto the substrate by etching, by heating inside the chamber after etching a silicon oxide film on the substrate.

Description

  Embodiments described herein relate generally to an etching apparatus.

As an apparatus for etching a silicon oxide film formed on a substrate, there is an etching apparatus for etching a silicon oxide film using NH ₃ gas and HF gas. In this etching apparatus, etching is performed at 100 ° C. or lower in order to perform uniform etching.

When etching using NH ₃ gas and HF gas is performed in the etching apparatus, ammonium silicofluoride adheres on the substrate. For this reason, it is necessary to remove ammonium silicofluoride on the substrate after etching. As a method of removing ammonium silicofluoride from the substrate, there is a method of heating the substrate and sublimating ammonium silicofluoride. In order to apply this method, a vacuum chamber for heating is required separately from the etching unit, and the apparatus configuration is complicated. For this reason, an apparatus for removing ammonium silicofluoride from a substrate with a simple configuration is required.

JP 2002-289593 A JP-T-2006-523379

  The problem to be solved by the present invention is to provide an etching apparatus capable of removing ammonium silicofluoride from a substrate with a simple structure.

According to the embodiment, an etching apparatus is provided. The etching apparatus includes an etching unit that etches a silicon oxide film on a substrate at 100 ° C. or lower using NH ₃ gas and HF gas in the chamber, and a transport that transports the substrate between the load lock chamber and the etching unit. And a robot. The etching unit supports the substrate and functions as a lower electrode, and supports the substrate. The etching unit is disposed at a position facing the substrate supporting table, functions as an upper electrode, and uses the NH ₃ gas and the HF gas as the substrate. A gas supply unit that supplies gas to the support base; and an exhaust pipe that exhausts the gas in the chamber. In addition, the etching unit is disposed in the vicinity of the window portion of the transparent member disposed as a part of the wall surface of the chamber at a position on the outer peripheral side in the chamber from the gas supply unit, And a heating unit that heats the inside of the chamber. The heating unit sublimates ammonium silicofluoride deposited on the substrate by etching by heating the inside of the chamber after the silicon oxide film on the substrate is etched.

FIG. 1 is a diagram illustrating a configuration of an etching apparatus according to the embodiment. FIG. 2 is a diagram illustrating a configuration of an etching unit included in the etching apparatus. FIG. 3 is a flowchart showing an etching process procedure of the etching apparatus according to the embodiment. FIG. 4 is a diagram showing a configuration of an etching apparatus including a sublimation chamber and a cooling chamber. FIG. 5 is a flowchart showing an etching process procedure of an etching apparatus provided with a sublimation chamber and a cooling chamber.

  Hereinafter, an etching apparatus according to an embodiment will be described in detail with reference to the accompanying drawings. In addition, this invention is not limited by this embodiment.

(Embodiment)
FIG. 1 is a diagram illustrating a configuration of an etching apparatus according to the embodiment. FIG. 1 shows a perspective view (partially perspective view) of the etching apparatus 1. The etching apparatus 1 is an apparatus that etches a silicon oxide film formed on a substrate such as a wafer (a substrate 33 described later). The etching apparatus 1 includes a load lock chamber 2, etching units 3A and 3B, a transfer chamber 4, and transfer robots 11A and 12A.

  The FOUP (Front-Opening Unified Pod) 5 is a transport container (transport carrier) that can store the substrate 33. When the substrate 33 is etched, the FOUP 5 containing one to a plurality of substrates 33 is placed on the FOUP placement table (not shown) of the etching apparatus 1. The FOUP mounting table is disposed in the vicinity of the substrate carry-in / out entrance, and the substrate 33 in the FOUP 5 is carried into the etching apparatus 1 and the substrate 33 is carried out into the FOUP 5 after etching.

  The transfer robots 11 </ b> A and 12 </ b> A are robots that transfer the substrate 33. The transfer robot 11 </ b> A is disposed between the FOUP mounting table and the load lock chamber 2. The transfer robot 11 </ b> A takes out the substrate 33 from the FOUP 5 and transfers it to the load lock chamber 2 when starting etching the substrate 33. Further, when the etching of the substrate 33 is completed, the transfer robot 11A takes out the substrate 33 from the load lock chamber 2 and transfers it to the FOUP 5.

  The load lock chamber 2 is disposed adjacent to the transfer chamber 4. The load lock chamber 2 evacuates the interior of the load lock chamber 2 when the substrate 33 is loaded when etching of the substrate 33 is started.

The etching units 3 </ b> A and 3 </ b> B are disposed adjacent to the transfer chamber 4. The etching units 3A and 3B have an etching processing chamber (chamber 35 described later) for etching the silicon oxide film formed on the substrate 33. The etching parts 3A and 3B etch the silicon oxide film at about 100 ° C. or less using NH ₃ gas and HF gas.

  The etching units 3A and 3B of the present embodiment remove the ammonium silicofluoride adhering to the substrate 33 when the silicon oxide film is etched from the substrate 33 in the etching processing chamber. Specifically, the etching units 3A and 3B sublimate ammonium silicofluoride by heating the substrate 33. In addition, the etching units 3 </ b> A and 3 </ b> B cool the substrate 33 in the etching processing chamber after sublimating ammonium silicofluoride from the substrate 33.

  The transfer chamber 4 is disposed adjacent to the load lock chamber 2 and the etching parts 3A and 3B. The transfer chamber 4 is a relay chamber that relays the transfer of the substrate 33 between the load lock chamber 2 and the etching units 3A and 3B.

  A transfer robot 12 </ b> A is disposed in the transfer chamber 4. When etching the substrate 33 by the etching unit 3A, the transfer robot 12A transfers the substrate 33 from the load lock chamber 2 to the etching unit 3A. When etching the substrate 33 by the etching unit 3B, the transfer robot 12A transfers the substrate 33 from the load lock chamber 2 to the etching unit 3B.

  When the etching, heating (sublimation), and cooling in the etching unit 3A are completed, the transfer robot 12A transfers the substrate 33 from the etching unit 3A to the load lock chamber 2. When the etching, heating, and cooling in the etching unit 3B are completed, the transfer robot 12A transfers the substrate 33 from the etching unit 3B to the load lock chamber 2.

  When etching the substrate 33 by the etching apparatus 1, the substrate 33 is transferred from the FOUP 5 to the load lock chamber 2 (ST1), and transferred from the load lock chamber 2 to the etching unit 3A (ST2).

  When the etching, heating, and cooling of the substrate 33 are completed, the substrate 33 is transferred from the etching unit 3A to the load lock chamber 2 (ST3), and then the substrate 33 is transferred from the load lock chamber 2 to the FOUP 5 (ST4). ).

  Next, the configuration of the etching parts 3A and 3B will be described. Since the etching parts 3A and 3B have the same configuration, the configuration of the etching part 3A will be described here.

  FIG. 2 is a diagram illustrating a configuration of an etching unit included in the etching apparatus. FIG. 2 shows a cross-sectional configuration of the etching portion 3A. The etching unit 3A has a chamber 35 as an etching processing chamber. A shower head (gas supply unit) 37 functioning as an upper electrode is provided on the upper side of the chamber 35, and a lower electrode is provided on the lower side. A functioning substrate support 32 is provided. The shower head 37 is disposed at a position facing the substrate support base 32.

  Pipes 45 and 46 for supplying gas sent from the gas cylinders 61 to 65 are connected to the chamber 35. The shower head 37 is provided with a plurality of gas discharge ports penetrating in the thickness direction of the plate, and the gas sent from the pipes 45 and 46 is introduced into the chamber 35 from the gas discharge ports. With this configuration, the gas can be efficiently flowed to the substrate 33 on the substrate support base 32, and the substrate 33 can be uniformly etched.

The gas cylinders 61 to 65 store NH ₃ gas, N ₂ gas, H ₂ gas, HF gas, and N ₂ gas, respectively. NH ₃ gas, N ₂ gas, and H ₂ gas in the gas cylinders 61 to 63 are sent into the chamber 35 of the etching unit 3A through the pipe 45. The HF gas and N ₂ gas in the gas cylinders 64 and 65 are sent into the chamber 35 of the etching unit 3A through the pipe 46.

NH ₃ gas and HF gas are etching gases used when etching the silicon oxide film on the substrate 33, and H ₂ gas is a gas used when removing ammonium silicofluoride from the substrate 33. The H ₂ gas is also used when the substrate 33 is cooled. Further, the N ₂ gas in the gas cylinder 62 is used when driving out the gas in the pipe 45 (N ₂ purge), and the N ₂ gas in the gas cylinder 64 is used when driving out the gas in the pipe 46 (N ₂ purge). Used for.

  A valve 41, a mass flow 42, and a valve 41 are arranged between the gas cylinders 61 to 63 and the pipe 45, respectively. Similarly, a valve 41, a mass flow 42, and a valve 41 are disposed between the gas cylinders 64 and 65 and the pipe 46, respectively.

  A pipe (exhaust pipe) 47 for discharging gas is connected to the bottom surface side of the chamber 35. In the piping 47, an orifice 27, an exhaust port valve 28, a filter 29, and a vacuum pump 30 are arranged.

  The orifice 27 measures the flow rate of the gas flowing in the piping 47, and the exhaust port valve 28 controls the flow rate of the gas flowing in the piping 47. The filter 29 removes a predetermined component from the gas flowing in the pipe 47, and the vacuum pump 30 evacuates the chamber 35 by discharging the gas in the pipe 47.

  Moreover, the etching part 3A of this embodiment is provided with the lamp heater 21, the window part 22 comprised with the transparent member, and the raising / lowering part (moving part) 36 in the upper part side. The lamp heater 21 is a heater that heats the inside of the chamber 35, and is disposed outside the chamber 35. The window portion 22 is disposed on a part of the wall surface constituting the chamber 35. With this configuration, the lamp heater 21 is adjacent to the chamber 35 in a substantially vacuum state via the window portion 22.

The raising / lowering part 36 is connected to the lamp heater 21 and raises / lowers the lamp heater 21 as needed. Specifically, the elevating part 36 brings the lamp heater 21 closer to the window part 22 when sublimating ammonium silicofluoride, and moves the lamp heater 21 away from the window part 22 when cooling the substrate 33. The elevating unit 36 may include a mechanism for cooling the periphery of the window 22 with N ₂ gas or dry air when the lamp heater 21 is moved away from the window 22.

  When the substrate 33 is heated, the lamp heater 21 is turned on and moves to the window portion 22 side. Thereby, the lamp heater 21 heats the inside of the chamber 35 through the window portion 22, and as a result, the substrate 33 is heated.

  On the other hand, while the substrate 33 is not heated, the lamp heater 21 is turned off and moves away from the window portion 22. Thereby, the remaining heat of the lamp heater 21 is prevented from being transmitted into the chamber 35 through the window portion 22.

  The window part 22 is comprised using the sapphire member strong to a fluoride, an alumina-type glass member, etc. The lamp heater 21 and the window portion 22 of the present embodiment are arranged at positions outside the substrate support base 32 (substrate 33) when the chamber 35 is viewed from the upper surface side. In other words, the lamp heater 21 and the window portion 22 are disposed on the outer peripheral side of the wall surface of the chamber 35 with respect to the gas delivery ports of the pipes 45 and 46. Thus, the window portion 22 is arranged as a part of the wall surface of the chamber at a position on the outer peripheral side in the chamber 35 with respect to the shower head 37.

  With this arrangement position, the inside of the chamber 35 can be heated by the lamp heater 21 without hindering the flow of gas sent from the pipes 45 and 46 to the substrate 33 and the flow of gas sent from the board 33 to the pipe 47. it can. With this configuration, it is possible to sublimate ammonium silicofluoride and cool the substrate 33 in the chamber 35 while etching the substrate 33 uniformly. Note that the lamp heater 21 and the window portion 22 may be disposed on the bottom side or the side surface portion of the chamber 35 as long as they are peripheral portions that do not hinder gas supply or gas discharge to the substrate 33 in the chamber 35.

  A heat exchanger 34 for heating the chamber 35 is disposed in the wall surface of the chamber 35. In the chamber 35, a substrate support 32 and a temperature sensor 24 are disposed. The substrate support table 32 is a table on which the substrate 33 is placed horizontally, and is arranged below the outlet of the gas fed from the pipes 45 and 46.

  A heater 31 is disposed inside the substrate support base 32 and heats the substrate 33 from the bottom surface side of the substrate 33. The heater 31 is, for example, a sheath heater or a carbon heater. Further, a temperature sensor 24 is disposed in the vicinity (here, the bottom surface portion) of the substrate support base 32. The temperature sensor 24 is a sensor that detects the temperature of the substrate 33.

  In the etching section 3A, the temperature of the substrate 33 when etching the silicon oxide film is set to about 70 to 100 ° C., and the temperature of the substrate 33 when sublimating ammonium silicofluoride is set to about 100 to 200 ° C. Moreover, after sublimating ammonium silicofluoride, the substrate 33 is cooled so that the temperature of the substrate 33 becomes about 70 to 100 ° C. Based on the temperature detected by the temperature sensor 24, the etching unit 3A heats the heater 31 and the heat exchanger 34 so that the temperature of the substrate 33 becomes a desired temperature.

  The etching unit 3 </ b> A includes a substrate elevator 26 and an inter-chamber gate 23. The substrate elevator 26 is disposed on the bottom side of the etching unit 3 </ b> A, and extends from the outside of the chamber 35 to the inside of the chamber 35 via a bellows (bellows) 25. The substrate elevator 26 raises and lowers the substrate 33 on the substrate support base 32 through a through hole provided in the substrate support base 32.

  The inter-chamber gate 23 is disposed on the side surface of the chamber 35. The inter-chamber gate 23 is opened when the substrate 33 is transported between the etching unit 3 </ b> A and the transfer chamber 4, and is closed when the substrate 33 is etched.

  Next, an etching process procedure in the etching apparatus 1 will be described. FIG. 3 is a flowchart showing an etching process procedure of the etching apparatus according to the embodiment. When the FOUP 5 is placed on the FOUP mounting table, the transfer robot 11A takes out the substrate 33 from the FOUP 5 (Step S10), and carries the substrate 33 into the load lock chamber 2 (Step S20).

  The load lock chamber 2 evacuates the load lock chamber 2. Thereafter, the transfer robot 12A carries the substrate 33 from the load lock chamber 2 to the etching unit 3A or the etching unit 3B (step S30). Here, a case where the substrate 33 is transported to the etching unit 3A will be described.

When the substrate 33 is carried into the chamber 35 of the etching unit 3A, the etching unit 3A performs an etching process on the substrate 33 (step S40). When etching the substrate 33, the NH ₃ gas in the gas cylinder 61 and the HF gas in the gas cylinder 64 are connected to the pipe 45 in a state where the temperature of the substrate 33 is set to 100 ° C. or lower (for example, 70 ° C.) in the chamber 35. Through the chamber 35. Then, the silicon oxide film on the substrate 33 is etched using NH ₃ gas and HF gas. Note that when the substrate 33 is etched, the lamp heater 21 is in an OFF state.

After etching the substrate 33, lamp heating / sublimation processing by the lamp heater 21 is performed in the chamber 35 (step S50). Specifically, H ₂ gas in the gas cylinder 63 is sent into the chamber 35 via the pipe 45. At this time, the exhaust valve 28 is closed simultaneously with the introduction of the H ₂ gas into the chamber 35, thereby bringing the inside of the chamber 35 into an H ₂ gas sealed state at a pressure of 10 Pa to 1000 Pa (for example, 100 Pa). In other words, H ₂ gas is supplied into the chamber 35 until the pressure in the chamber 35 reaches 10 Pa to 1000 Pa.

Further, the elevating part 36 moves the lamp heater 21 to the vicinity of the window part 22, and the lamp heater 21 is turned on. Thereby, the surface of the substrate 33 is heated to 100 to 200 ° C. by the convection of H ₂ gas in a state where the pressure in the chamber 35 is 10 to 1000 Pa.

By maintaining this state for a predetermined time, the etching unit 3A sublimates and removes ammonium silicofluoride generated when the silicon oxide film is etched in the chamber 35. The etching unit 3A may or may not stop the feeding of the NH ₃ gas and the HF gas into the chamber 35 when feeding the H ₂ gas into the chamber 35.

After sublimating ammonium silicofluoride, H ₂ purge cooling processing is performed in the chamber 35 (step S60). Specifically, the exhaust valve 28 is opened while the introduction of H ₂ gas is continued. Further, the lamp heater 21 is turned off, and the elevating part 36 moves the lamp heater 21 away from the window part 22 side. As a result, the temperature of the inside of the chamber 35 or the surface of the substrate 33 is lowered to the etching temperature (100 ° C. or lower). When the substrate 33 is cooled, the lamp heater 21 may be cooled with N ₂ gas or the like.

  Thereafter, the transfer robot 12A unloads the substrate 33 from the etching unit 3A (step S70), and loads the substrate into the load lock chamber 2 (step S80). Further, the transfer robot 11A unloads the substrate 33 from the load lock chamber 2, and stores the substrate 33 in the FOUP 5 (step S90).

  As described above, the etching apparatus 1 does not use a sublimation chamber (heating / sublimation chamber) having a configuration different from that of the etching units 3A and 3B, and etches the silicon oxide film in the etching units 3A and 3B. Sublimation and cooling of the substrate 33 can be performed.

  Next, the structure of the etching apparatus when the sublimation of ammonium silicofluoride and the cooling of the substrate 33 are performed by an apparatus other than the etching units 3A and 3B will be described. In this case, the etching apparatus includes a sublimation chamber for sublimating ammonium silicofluoride and a cooling chamber (cooling stage) for cooling the substrate 33.

  FIG. 4 is a diagram showing a configuration of an etching apparatus including a sublimation chamber and a cooling chamber. The etching apparatus 100 shown in the figure includes a load lock chamber 2, etching units 3X and 3Y, a transfer chamber 4, transfer robots 11B and 12B, a cooling chamber 51, and a sublimation chamber 52.

  In the etching apparatus 100, the etching units 3X and 3Y perform etching of the silicon oxide film, and the sublimation chamber 52 performs heating and sublimation of ammonium silicofluoride. In addition, the substrate 33 is cooled in the cooling chamber 51.

  The transport robot 11B transports the substrate 33 from the FOUP 5 to the load lock chamber 2, transports the substrate 33 from the load lock chamber 2 to the cooling chamber 51, and transports the substrate 33 from the cooling chamber 51 to the FOUP 5.

  The transfer robot 12B transfers the substrate 33 from the load lock chamber 2 to the etching unit 3X or the etching unit 3Y, and transfers the substrate 33 from the etching unit 3X or the etching unit 3Y to the sublimation chamber 52. Further, the transfer robot 12 </ b> B transfers the substrate 33 from the sublimation chamber 52 to the load lock chamber 2.

  Here, a procedure for carrying the substrate 33 by the etching apparatus 100 will be described. In addition, since the same processing is performed in the etching units 3X and 3Y, a case where etching is performed in the etching unit 3X will be described here.

  When etching the substrate 33 by the etching apparatus 100, the substrate 33 is transferred from the FOUP 5 to the load lock chamber 2 (ST11). Thereafter, the substrate 33 is transferred from the load lock chamber 2 to the etching unit 3X (ST12), and the substrate 33 is etched by the etching unit 3X.

  When the etching of the substrate 33 is completed, the substrate 33 is transferred from the etching unit 3X to the sublimation chamber 52 (ST13), and ammonium silicofluoride is heated and sublimated in the sublimation chamber 52. Then, the substrate 33 is transferred from the sublimation chamber 52 to the load lock chamber 2 (ST14).

  Further, the substrate 33 is transferred from the load lock chamber 2 to the cooling chamber 51 (ST15) and cooled in the cooling chamber 51. Thereafter, the substrate 33 is transferred from the cooling chamber 51 to the FOUP 5 (ST16).

  As described above, in the etching apparatus 100, when performing etching of the silicon oxide film, sublimation of ammonium silicofluoride, and cooling of the substrate 33, six transports from ST11 to ST16 are performed. On the other hand, in the etching apparatus 1, when carrying out etching of the silicon oxide film, sublimation of ammonium silicofluoride, and cooling of the substrate 33, four transports from ST1 to ST4 may be performed. Therefore, by using the etching apparatus 1, it is possible to reduce the number of times the substrate 33 is transferred and the transfer distance.

  Next, an etching process procedure in the etching apparatus 100 including the sublimation chamber 52 and the cooling chamber 51 will be described. FIG. 5 is a flowchart showing an etching process procedure of an etching apparatus provided with a sublimation chamber and a cooling chamber. FIG. 5 shows an etching process procedure (left flow) of the etching apparatus 100 including the sublimation chamber 52 and the cooling chamber 51 and an etching process procedure (right flow) of the etching apparatus 1 including the etching units 3A and 3B. ing. In the following description, each processing procedure for etching the substrate 33 using the etching unit 3X of the etching apparatus 100 and for etching the substrate 33 using the etching unit 3A of the etching apparatus 1 will be described.

  The etching apparatus 100 etches the substrate 33 by the same process as the etching apparatus 1 (Steps S10 to S40). Specifically, the substrate 33 is taken out from the FOUP 5 (step S110), the substrate 33 is loaded into the load lock chamber 2 (step S120), and the substrate 33 is loaded from the load lock chamber 2 into the etching unit 3X (step S120). S130). Thereafter, in the etching apparatus 100, the silicon oxide film is etched in the etching unit 3X (step S140).

Thereafter, in the etching apparatus 1, lamp heating / sublimation processing by the lamp heater 21 is performed in the etching unit 3A (step S50), and then H ₂ purge cooling processing is performed in the etching unit 3A (step S60). Then, the substrate 33 is unloaded from the etching unit 3A (step S70).

  In the etching apparatus 100, after the silicon oxide film is etched by the etching unit 3X, the substrate 33 is unloaded from the etching unit 3X (step S150), and the substrate 33 is loaded into the sublimation chamber 52 (step S160). ). Then, lamp heating / sublimation processing is performed in the sublimation chamber 52 (step S170).

  Thereafter, the substrate 33 is carried out from the sublimation chamber 52 (step S180), and the substrate 33 is carried into the load lock chamber 2 (step S190). Then, the substrate 33 is cooled in the cooling chamber 51 (step S200), and then the substrate 33 is stored in the FOUP 5 (step S210).

  On the other hand, in the etching apparatus 1, the substrate 33 unloaded from the etching unit 3A is loaded into the load lock chamber 2 (step S80), and then the substrate 33 is stored in the FOUP 5 (step S90). As described above, in the etching apparatus 1, the processes in steps S <b> 160 to S <b> 180 and S <b> 200 are omitted instead of the processes in steps S <b> 50 and S <b> 60 as compared with the etching apparatus 100.

  When manufacturing a semiconductor device (semiconductor integrated circuit), a semiconductor circuit pattern is formed on the substrate 33. At this time, film formation processing, lithography processing, etching processing using the etching apparatus 1 and the like are performed on the substrate 33.

  Specifically, after a film to be patterned is formed on the substrate 33, a resist is applied on the film. Then, a resist pattern is formed using the mask on which the mask pattern is formed. The resist pattern forming process by the lithography process may use optical lithography or imprint lithography.

  After forming the resist pattern, a lower layer film (for example, a silicon oxide film) of the resist pattern is etched by the etching apparatus 1 or the like, and thereby an actual pattern corresponding to the resist pattern is formed on the substrate 33. When manufacturing a semiconductor device, a film formation process, a lithography process, an etching process, and the like are repeated for each layer.

  As described above, the etching apparatus 1 performs etching of the silicon oxide film, sublimation of ammonium silicofluoride, and cooling of the substrate 33 by the etching units 3A and 3B, so that the transport time of the substrate 33 can be shortened.

  In addition, since the transport time of the substrate 33 is shortened, it is possible to improve the tact time when performing etching. Moreover, since the conveyance path | route of the board | substrate 33 becomes short, it becomes possible to restrain the installation area (footprint) of the etching apparatus 1 small.

  Further, since the cooling chamber 51 and the sublimation chamber 52 are not necessary, the substrate 33 can be etched with a simple configuration. Therefore, the installation cost of the etching apparatus 1 can be kept low. In addition, since the cooling chamber 51 and the sublimation chamber 52 are not necessary, the installation area of the etching apparatus 1 can be reduced.

  Further, when sublimating ammonium silicofluoride, the lamp heater 21 heats the inside of the chamber 35 in a state where the lamp heater 21 is moved to the vicinity of the window portion 22, so that the heating efficiency is improved. Further, when the substrate 33 is cooled, the cooling efficiency is improved because the lamp heater 21 is kept away from the window portion 22.

Further, when the substrate 33 is cooled, since the H ₂ gas is allowed to flow into the chamber 35 while the substrate 33 remains in the chamber 35, the temperature in the chamber 35 (the temperature of the substrate 33) can be reduced in a short time. It is possible to return to the temperature during the etching process.

  In the present embodiment, the case where the etching apparatus 1 includes two etching units 3A and 3B has been described. However, the etching apparatus 1 may include one etching unit or three or more etching units. May be provided.

In the present embodiment, the case where the substrate 33 is cooled in the etching units 3A and 3B has been described. However, the substrate 33 may be cooled by another apparatus (such as a cooling chamber). In this case, etching of the silicon oxide film and sublimation of ammonium silicofluoride are performed by the etching units 3A and 3B, and the substrate 33 is cooled by another apparatus. In addition, the gas used for sublimation of ammonium silicofluoride and cooling of the substrate 33 is not limited to H ₂ gas, and other gases (N ₂ gas, He gas, etc.) may be used as long as they have high thermal efficiency. .

As described above, according to the embodiment, etching, sublimation of ammonium silicofluoride, and cooling of the substrate 33 are performed in the etching portions 3A and 3B. Therefore, the ammonium silicofluoride is removed from the substrate 33 with a simple configuration. Is possible.
Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  DESCRIPTION OF SYMBOLS 1,100 ... Etching apparatus, 2 ... Load lock chamber, 3A, 3B ... Etching part, 11A, 12A ... Transfer robot, 21 ... Lamp heater, 22 ... Window part, 24 ... Temperature sensor, 30 ... Vacuum pump, 31 ... Heater 32 ... Substrate support, 33 ... Substrate, 34 ... Heat exchanger, 35 ... Chamber, 37 ... Shower head, 45, 46, 47 ... Piping, 51 ... Cooling chamber, 52 ... Sublimation chamber, 61-65 ... Gas cylinder.

Claims (10)

An etching portion for etching a silicon oxide film on the substrate at 100 ° C. or lower using NH ₃ gas and HF gas in the chamber;
A transfer robot for transferring a substrate between the load lock chamber and the etching unit;
With
The etched portion is
A substrate support that supports the substrate and functions as a lower electrode;
A gas supply unit that is disposed at a position facing the substrate support and functions as an upper electrode and supplies the NH ₃ gas and the HF gas to the substrate support;
An exhaust pipe for exhausting the gas in the chamber;
A window portion of a transparent member disposed as a part of the wall surface of the chamber at a position closer to the outer peripheral side in the chamber than the gas supply unit;
A heating unit disposed in the vicinity of the window to heat the chamber;
A moving unit that moves the heating unit in the vicinity of the window;
Have
The heating unit is
After the silicon oxide film on the substrate is etched, the inside of the chamber is heated to sublimate ammonium silicofluoride attached on the substrate by etching,
When sublimating the ammonium silicofluoride,
The exhaust pipe stops exhausting the gas, and the gas supply unit supplies a first gas to be sealed in the chamber,
After sublimating the ammonium silicofluoride,
The exhaust pipe restarts exhaust of the gas, and the gas supply unit cools the substrate to 100 ° C. or less by supplying a second gas into the chamber,
The moving unit moves the heating unit closer to the window when sublimating the ammonium silicofluoride, and keeps the heating unit away from the window when cooling the substrate.
The first gas and the second gas are H ₂ gas,
The window portion is configured using a sapphire member,
The sublimation temperature is 100 ° C. to 200 ° C. An etching portion for etching a silicon oxide film on the substrate at 100 ° C. or lower using NH ₃ gas and HF gas in the chamber;
A transfer robot for transferring a substrate between the load lock chamber and the etching unit;
With
The etched portion is
A substrate support that supports the substrate and functions as a lower electrode;
A gas supply unit that is disposed at a position facing the substrate support and functions as an upper electrode and supplies the NH ₃ gas and the HF gas to the substrate support;
An exhaust pipe for exhausting the gas in the chamber;
A window portion of a transparent member disposed as a part of the wall surface of the chamber at a position on the outer peripheral side in the chamber from the gas supply portion;
A heating unit disposed in the vicinity of the window to heat the chamber;
Have
The heating unit is
An etching apparatus characterized in that after the silicon oxide film on the substrate is etched, the inside of the chamber is heated to sublimate ammonium silicofluoride adhering to the substrate by etching. When sublimating the ammonium silicofluoride,
The etching apparatus according to claim 2, wherein the exhaust pipe stops exhausting the gas, and the gas supply unit supplies a first gas to be sealed in the chamber. After sublimating the ammonium silicofluoride,
4. The exhaust pipe restarts the gas, and the gas supply unit cools the substrate to 100 ° C. or less by supplying a second gas into the chamber. The etching apparatus as described. The etching apparatus according to claim 4, wherein the first gas and the second gas are H ₂ gas.   The said window part is comprised using the sapphire member, The etching apparatus as described in any one of Claims 1-5 characterized by the above-mentioned.   The said sublimation temperature is 100 to 200 degreeC, The etching apparatus as described in any one of Claims 1-6 characterized by the above-mentioned. The etching part further comprises a moving part that moves the heating part in the vicinity of the window part,
2. The moving unit moves the heating unit closer to the window when sublimating the ammonium silicofluoride, and moves the heating unit away from the window when cooling the substrate. The etching apparatus as described in any one of -7.   The etching apparatus according to claim 4, wherein the gas supply unit cools the substrate to a temperature of the substrate when the silicon oxide film is etched. When sublimating the ammonium silicofluoride,
The etching apparatus according to claim 3, wherein the gas supply unit supplies the first gas until a pressure in the chamber becomes 10 Pa to 1000 Pa.

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