JP2007043022A - Apparatus and method for semiconductor processing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a semiconductor processing apparatus which eliminates a defect caused from a reaction product produced in a reaction pipe, and controls deterioration of processing performance; and to provide a semiconductor processing method. <P>SOLUTION: An MOCVD apparatus 10 includes a chamber 11; a reaction pipe 12 where a processing space 50 is located with a substrate 14 positioned, and which is located in the chamber 11; and a pyrometer 25 which is located outside the reaction pipe 12, and observes the inside of the reaction pipe 12. A reaction gas for processing the substrate 14 flows through the processing space 50. An opening 27 is formed between the pyrometer 25 and the substrate 14 in the reaction pipe 12. Moreover, the MOCVD apparatus 10 has a partition 28 which is located between the opening 27 and the pyrometer 25, and forms a closed space 70 communicating with the processing space 50 through the opening 27. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention generally relates to a semiconductor processing apparatus and a semiconductor processing method, and more specifically, a reaction gas is caused to flow in a reaction tube in which a processing target is installed, and film formation and etching are performed on the processing target. The present invention relates to a semiconductor processing apparatus that performs processing such as oxidation, and a semiconductor processing method using the apparatus.

  2. Description of the Related Art A chemical vapor deposition (CVD) apparatus is one of semiconductor processing apparatuses that forms a film using a gas, and has been widely used in the field of semiconductor manufacturing. In this vapor phase growth apparatus, a substrate to be formed is heated in advance, and one or more kinds of material gases are flowed toward the substrate. The material gas heated around the substrate causes a chemical reaction and forms a film on the substrate.

  FIG. 10 is a cross-sectional view showing a conventional vapor phase growth apparatus. Referring to FIG. 10, in the vapor phase growth apparatus, the gas flow greatly affects the quality of the film formation. For this reason, the reaction tube 102 made of quartz or the like for controlling the gas flow is accommodated in a metal hermetic chamber 101, and the substrate 104 is disposed in the reaction tube 102. The material gas is supplied from the material gas supply device 112 to the space 120 in the reaction tube 102 through the material gas introduction tube 110. The material gas flows as a laminar flow in the space 120 and is discharged from the material gas discharge pipe 111 to the outside.

  The reaction tube 102 does not have a gas sealing ability. Therefore, the material gas leaking from the reaction tube 102 stays in the space 130 outside the reaction tube 102 and inside the chamber 101. In the vapor phase growth apparatus in the figure, a relatively small amount of inert gas is introduced into the space 130 from the inert gas supply port 113 so that the material gas leaking from the reaction tube 102 does not adversely affect the film formation. Has been. The inert gas flows through the space 130 and is then discharged to the outside from the inert gas outlet 114.

  On the other hand, in such a vapor phase growth apparatus, it is important that the temperature of the substrate 104, the thickness of the formed film, and the like can be measured during processing in order to appropriately control the film formation. For this reason, as shown in FIG. 10, a non-contact sensor 115 such as a pyrometer for measuring temperature and an ellipsometer for measuring film thickness is installed outside the chamber 101.

  When the non-contact sensor 115 is used, the measurement of the substrate 104 is performed through the view port 116 provided on the wall surface of the chamber 101 and the reaction tube 102 made of transparent quartz. However, in the vapor phase growth apparatus, unnecessary reaction products are generated in the reaction tube 102 due to the flow of the material gas. For this reason, generally, the deposit 105 is generated at a place other than the surface of the substrate such as the inner wall of the reaction tube 102 or the substrate tray 107. In particular, this tendency becomes remarkable in an organic metal vapor phase growth (MOCVD) apparatus using an organic metal gas as one kind of material gas.

In addition, Japanese Patent Laid-Open No. 3-75389 discloses a dry etching apparatus for preventing attenuation of input light to an end point detection sensor and improving end point detection accuracy (Patent Document 1). . Japanese Utility Model Laid-Open No. 5-764 discloses a vapor deposition apparatus for the purpose of suppressing the influence of precipitates generated in the reaction vessel in the film formation process and increasing the measurement accuracy of the substrate temperature. (Patent Document 2). Japanese Patent Application Laid-Open No. 61-163632 discloses a molecular beam epitaxial growth apparatus aimed at preventing the glass plate on the viewport from being contaminated by molecular beams and preventing the failure of the apparatus. (Patent Document 3).
JP-A-3-75389 Japanese Utility Model Publication No. 5-764 JP 61-163632 A

  As described with reference to FIG. 10, when the deposit 105 is generated on the inner wall of the reaction tube 102, the surface of the reaction tube 102, which is transparent at this point, eventually becomes cloudy. For this reason, the transmission of the observation light input to the non-contact sensor 115 is hindered by the surface of the reaction tube 102, and there arises a problem that the measurement by the non-contact sensor 115 is impossible to measure or involves a large error in the measurement.

  As a method for preventing the occurrence of such deposits, a method such as using heating as disclosed in Patent Document 1 or introducing an inert gas as disclosed in Patent Document 2 is used. There is.

  However, when the reaction tube 102 is heated, the temperature distribution in the vicinity of the substrate 104 is disturbed, which may adversely affect film growth on the substrate. Moreover, there is a possibility that observation is hindered by a heater provided for heating.

  Further, in the method of introducing the inert gas, the inert gas flows in the space 120 in the reaction tube 102, so that the flow of the material gas is disturbed in the vicinity of the substrate 104, which adversely affects the film growth on the substrate. There is a fear. In addition, it may be difficult to install an inert gas inlet immediately above the substrate on which the generation of deposits is desired. For this reason, generation | occurrence | production of a deposit | attachment cannot fully be suppressed in a desired position, or it will be necessary to provide the introduction mechanism of an inert gas separately.

  On the other hand, the molecular beam epitaxial growth apparatus disclosed in Patent Document 3 is an MBE (molecular beam epitaxy) apparatus that does not involve a gas flow in the processing of a substrate. FIG. 11 is a cross-sectional view showing the molecular beam epitaxial growth apparatus disclosed in Patent Document 3. As shown in FIG.

  Referring to FIG. 11, this apparatus is provided with a shroud 207 for cooling and adsorbing the gas to be evaporated and a view port 204 protruding outside from the chamber 201 in a space in the chamber 201. A substrate 210 is accommodated in the space in the chamber 201. A glass plate 205 is provided on the bottom surface of the viewport 204. The inside of the apparatus is observed through the glass plate 205 by an infrared thermometer 206 installed outside the chamber 201.

The apparatus further includes a cylinder 209 that protrudes from the shroud 207 into the space in the chamber 201 and has an opening 211 formed therein. The opening 211 opens to a size that regulates the solid angle at which the center point 212 of the substrate 210 is viewed through the glass plate 205. The inside of the chamber 201 is set to an ultrahigh vacuum molecular flow region of 10 ⁻⁸ Pa or less, for example. For this reason, the existence density of gas molecules is low in the chamber 201, and the interaction between molecules does not work greatly. For this reason, even if gas molecules enter the closed space surrounded by the cylinder 209, the resistance force does not act. Further, since the inside of the chamber 201 is under an ultra-high vacuum, the deposits fly linearly regardless of the gas flow.

  When the structure of such an MBE apparatus is to be diverted to the vapor phase growth apparatus shown in FIG. 10, the cylinder 209 is arranged so as to protrude from the reaction tube 102 in FIG. In this case, since the reaction tube 102 is a functional component for keeping the flow of the material gas rectified, the cylinder 209 protruding into the space 120 disturbs the flow of the material gas. For this reason, there exists a possibility that the film-forming performance may fall.

  FIG. 12 is a cross-sectional view showing an improved example of the vapor phase growth apparatus in FIG. With reference to FIG. 12, a method of providing an opening 140 in the reaction tube 102 and performing measurement through the opening 140 is considered as another solution.

  However, there are flow of material gas and inert gas in the space 120 in the reaction tube 102 and the space 130 in the chamber 101, respectively. Therefore, simply forming the opening 140 in the reaction tube 102 causes the material gas flowing through the space 120 to flow out of the reaction tube 102 through the opening 140 (the gas flow indicated by the arrow 150 in the figure). The inert gas flowing in the space 130 flows into the reaction tube 102 through the opening 140 (gas flow indicated by an arrow 160 in the drawing). For this reason, the problem that the concentration of the material gas in the reaction tube 102 decreases in the vicinity of the opening 140 or the gas flow is disturbed occurs, which may adversely affect the film formation on the substrate 104.

  SUMMARY OF THE INVENTION An object of the present invention is to solve the above-described problems, and to provide a semiconductor processing apparatus and a semiconductor processing method capable of solving problems caused by reaction products generated in a reaction tube while suppressing a decrease in processing performance. It is.

  A semiconductor processing apparatus according to one aspect of the present invention defines a processing chamber, an internal space in which an object to be processed is installed, a reaction tube disposed in the processing chamber, and provided outside the reaction tube. A semiconductor processing apparatus including a non-contact sensor for observing the inside of a pipe. In the internal space, a reactive gas for processing the processing object flows. An opening is formed in the reaction tube between the non-contact sensor and the processing object. The semiconductor processing apparatus further includes a partition member that is provided between the opening and the non-contact sensor and forms a substantially closed space that communicates with the internal space through the opening.

  The substantially closed space referred to here includes a space that is strictly closed at a position excluding the opening, and a space that locally has a portion communicating with the outside through a minute gap or a hole.

  According to the semiconductor processing apparatus configured as described above, there is no positive gas flow in the substantially closed space formed by the partition member. For this reason, it is possible to suppress the flow of gas flowing through the opening between the internal space and the substantially closed space, and to prevent the reaction gas flow from being disturbed in the internal space. In addition, the observation of the object to be processed by the non-contact sensor is performed through an opening formed in the reaction tube. Therefore, the observation of the object to be processed is not hindered by the reaction product adhering to the inner wall of the reaction tube due to the flow of the reaction gas. Therefore, according to the present invention, it is possible to accurately observe the processing object without degrading the processing performance of the processing object.

  The reaction tube has a supply port through which the reaction gas is supplied to the internal space and an exhaust port through which the reaction gas is discharged from the internal space. The processing object is disposed between the supply port and the discharge port. According to the semiconductor processing apparatus configured as described above, the above effect can be obtained in the semiconductor processing apparatus in which the flow of the reaction gas for processing the processing object is formed from the supply port toward the discharge port. .

  In addition, an observation medium for observing the processing object is emitted in a bundle from the processing object toward the non-contact sensor. Preferably, the opening has an opening width equal to or larger than the cross-sectional area of the bundle of observation media on the opening surface of the opening. According to the semiconductor processing apparatus configured as described above, it is possible to prevent the observation medium from the processing target toward the non-contact sensor from being blocked by the periphery of the opening when passing through the opening. Thereby, an accurate observation of the processing object can be performed.

  Preferably, the semiconductor processing apparatus further includes a substantially cylindrical member that is disposed in the substantially closed space, surrounds the opening, and extends from the opening to the side opposite to the internal space. According to the semiconductor processing apparatus configured as described above, the pipe resistance of the gas flow passing through the opening is increased by providing the substantially cylindrical member. For this reason, the gas flow which passes an opening part can be suppressed more effectively.

  Preferably, the semiconductor processing apparatus includes a first pressure detection unit that detects a pressure in the internal space, a second pressure detection unit that detects a pressure in the substantially enclosed space, and a pressure adjustment that adjusts the pressure in the substantially enclosed space. And a section. The pressure adjustment unit is configured to reduce the pressure difference between the internal space and the substantially enclosed space based on the pressure values of the internal space and the substantially enclosed space detected by the first and second pressure detection units, respectively. Adjust pressure. According to the semiconductor processing apparatus configured as described above, it is possible to prevent a gas flow passing through the opening from being generated due to a pressure difference between the internal space and the substantially closed space.

  A semiconductor processing method according to the present invention is a semiconductor processing method using any of the semiconductor processing apparatuses described above, and observes a processing object with a non-contact sensor. According to the semiconductor processing method configured as described above, it is possible to precisely control the semiconductor device based on the observation result of the processing object that has been accurately performed.

  A semiconductor processing apparatus according to another aspect of the present invention defines a processing chamber, an internal space in which an object to be processed is installed, a reaction tube disposed in the processing chamber, and provided outside the reaction tube. It is a semiconductor processing apparatus provided with the light irradiation part which irradiates light toward a target object. In the internal space, a reactive gas for processing the processing object flows. In the reaction tube, an opening is formed between the light irradiation unit and the processing object. The semiconductor processing apparatus further includes a partition member that is provided between the opening and the light irradiation unit and forms a substantially closed space that communicates with the internal space through the opening.

In addition, about the substantially enclosed space said here, it understands similarly to said substantially enclosed space.
According to the semiconductor processing apparatus configured as described above, there is no positive gas flow in the substantially closed space formed by the partition member. For this reason, it is possible to suppress the flow of gas flowing through the opening between the internal space and the substantially closed space, and to prevent the reaction gas flow from being disturbed in the internal space. Moreover, the light irradiated by the light irradiation unit reaches the object to be processed through the opening. For this reason, the progress of light is not prevented by the reaction product adhering to the inner wall of the reaction tube due to the flow of the reaction gas. Therefore, according to the present invention, the light irradiated by the light irradiation unit can surely reach the processing object without causing deterioration of the processing performance for the processing object.

  As described above, according to the present invention, it is possible to provide a semiconductor processing apparatus and a semiconductor processing method that eliminate problems caused by reaction products generated in a reaction tube while suppressing a decrease in processing performance.

  Embodiments of the present invention will be described with reference to the drawings. In the drawings referred to below, the same or corresponding members are denoted by the same reference numerals.

(Embodiment 1)
FIG. 1 is a cross-sectional view showing an MOCVD apparatus according to Embodiment 1 of the present invention. Note that in this embodiment, the MOCVD apparatus illustrated in the drawing is described as an example; however, the present invention is not limited to this, and the present invention is not limited to this, for example, other film formation apparatuses, etching apparatuses, oxidation apparatuses, and surface modification apparatuses. The present invention can be applied to a semiconductor processing apparatus that involves gas flow.

  Referring to FIG. 1, an MOCVD apparatus 10 is an apparatus that forms a GaN (gallium nitride) film on a growth surface 14 a of a substrate 14. The MOCVD apparatus 10 includes a chamber 11, a reaction tube 12 that is disposed in the chamber 11 and defines a processing space 50, and a pyrometer 25 that is disposed outside the chamber 11. The processing space 50 is formed at a position surrounded by the inner wall 12 c of the reaction tube 12, and the substrate 14 that is a processing target is disposed in the processing space 50.

The chamber 11 has a housing shape and is made of, for example, aluminum or stainless steel. The atmosphere in the chamber 11 is placed in a viscous flow region having a pressure of about 10 ³ Pa to 10 ⁵ Pa.

  The reaction tube 12 is made of a material having resistance to a high temperature / reactive atmosphere such as quartz. The reaction tube 12 is formed in a cylindrical shape having a substantially rectangular cross section, and extends in the horizontal direction from one end 12m toward the other end 12n. A substrate holder 17 that holds the substrate 14 is provided at the bottom 12q of the reaction tube 12. The reaction tube 12 is positioned in the chamber 11 such that a gap exists between the top 12 p of the reaction tube 12 and the chamber 11.

  The substrate 14 is provided such that the growth surface 14 a is exposed to the processing space 50. The substrate 14 is provided in the middle between one end 12m and the other end 12n. A substrate heater 13 for heating the substrate 14 is provided on the back side of the substrate 14.

  In the present embodiment, the apparatus in which the substrate 14 is disposed so that the growth surface 14a faces vertically upward is described as an example. However, the present invention is not limited to this, and the growth surface 14a faces vertically downward. Thus, an apparatus in which the substrate 14 is arranged may be used. In this case, the MOCVD apparatus has a configuration in which the configuration shown in FIG. 1 is reversed upside down.

  A material gas supply unit 22 that supplies a material gas toward the processing space 50 is connected to one end 12 m of the reaction tube 12 via a material gas introduction tube 20. A material gas discharge pipe 21 that discharges the material gas from the processing space 50 is connected to the other end 12 n of the reaction tube 12. With such a configuration, the material gas flows in the direction indicated by the arrow 51 from the one end 12m to the other end 12n in the processing space 50, and passes through the vicinity of the substrate 14 during this time. When passing through the vicinity of the substrate 14, the material gas flows substantially parallel to the direction in which the growth surface 14 a extends.

  Although only one material gas introduction pipe 20 is shown in the figure, a plurality of material gas introduction pipes 20 may be provided.

  A space 60 is defined inside the chamber 11 and outside the reaction tube 12. An inert gas supply port 23 that supplies an inert gas toward the space 60 and an inert gas discharge port 24 that discharges the inert gas from the space 60 are connected to the chamber 11 at different locations.

  An opening 27 is formed in the reaction tube 12 between the substrate 14 and the pyrometer 25. The opening 27 is a position facing the substrate 14 and is formed immediately above the substrate 14. The opening 27 is formed at the top 12 p of the reaction tube 12. The opening 27 is formed between one end 12m and the other end 12n. The surface where the opening 27 opens into the processing space 50 extends in parallel with the direction indicated by the arrow 51 through which the material gas flows. The normal direction of the inner wall 12c of the reaction tube 12 where the opening 27 opens into the processing space 50 and the gas flow direction in the reaction tube 12 intersect each other.

  The chamber 11 is provided with a view port 26 located between the pyrometer 25 and the opening 27. The viewport 26 is made of, for example, quartz glass or sapphire glass. On the line connecting the substrate 14 and the pyrometer 25, the opening 27 and the viewport 26 are arranged in order from the substrate 14.

  A partition plate 28 is provided in the chamber 11 between the opening 27 and the pyrometer 25. The partition plate 28 is provided so as to connect the inner wall 11 c of the chamber 11 and the reaction tube 12 in the vicinity of the opening 27. The partition plate 28 has a cylindrical shape extending from the inner wall 11c toward the top surface 12a. The upper end of the partition plate 28 is fixed to the inner wall 11c by welding, and the lower end of the partition plate 28 is positioned at a position where there is almost no gap with the top surface 12a of the reaction tube 12. The partition plate 28 is provided so as not to protrude inside the processing space 50 but to protrude outside the processing space 50. With such a configuration, the partition plate 28 forms a closed space 70 that communicates with the processing space 50 through the opening 27 in the chamber 11.

  The cylindrical cross section of the partition plate 28 may be circular, polygonal, or other closed shape. Further, the method of fixing the partition plate 28 to the chamber 11 is not limited to welding, and various methods such as fastening and fitting can be used.

  The closed space 70 is formed in a substantially closed space with respect to the space inside the chamber 11 (that is, the space 60) and the space outside the chamber 11 other than the processing space 50. The closed space 70 is also formed in a space closed at the position excluding the opening 27 with respect to the processing space 50. Therefore, the gas in and out of the closed space 70 is limited to the opening 27. The volume of the closed space 70 is smaller than any volume of the processing space 50 and the space 60.

  The pyrometer 25 is installed above the chamber 11 at a position away from the chamber 11. The substrate 14 emits radiated light (many infrared rays) corresponding to the temperature. The emitted light sequentially passes through the opening 27 and the view port 26 and reaches the pyrometer 25. The pyrometer 25 receives the emitted light and analyzes the amount and / or wavelength thereof to calculate the temperature of the substrate 14.

When film formation is performed on the substrate 14, the material gases TMG (trimethylgallium) and NH ₃ are supplied from the material gas supply device 22 through the material gas introduction pipe 20 together with hydrogen or nitrogen as the carrier gas. It is introduced into the processing space 50. The material gas introduced into the processing space 50 flows from one end 12m to the other end 12n of the reaction tube 12 that restricts and rectifies the gas flow. During this time, the material gas flowing in the vicinity of the substrate 14 is heated by the substrate heater 13 and activated. As a result, the material gas causes an intermediate chemical reaction in the gas phase, and generates a predetermined GaN crystal film on the growth surface 14a when it contacts the surface of the substrate 14 that has reached a high temperature of about 1000 ° C. The material gas passes through the substrate 14 and is then discharged from the material gas discharge pipe 21 to the outside.

  Part of the material gas supplied at the time of film formation generates a reaction product composed of Ga, N, C, H, etc. in the processing space 50. The reaction product moves on the material gas flow in the reaction tube 12 and adheres to the inner wall 12 c of the reaction tube 12 and the surface of the substrate holder 17. As a result, the deposit 15 resulting from the gas flow in the reaction tube 12 is generated on the inner wall 12 c and the surface of the substrate holder 17.

  On the other hand, a relatively small amount of inert gas flows from the inert gas supply port 23 into the space 60 in the chamber 11 so that the material gas leaking from the reaction tube 12 stays and does not adversely affect the film formation. be introduced. The inert gas circulates through the space 60 and is then discharged to the outside from the inert gas outlet 24.

  In the present embodiment, unlike the processing space 50 and the space 60, gas is not forcibly supplied to the closed space 70. Further, since the closed space 70 has a relatively small volume, the closed space 70 is formed in a structure in which convection hardly occurs. In addition, since the entrance and exit of the gas in the enclosed space 70 is limited to the opening 27, the generation of gas flows that enter and exit the enclosed space 70 at the same time is suppressed. In addition, since the closed space 70 is formed in a substantially closed state, when gas flows in, the internal pressure of the closed space 70 rises and further gas inflow is prevented. Conversely, when gas flows out through the opening 27, the internal pressure of the closed space 70 decreases, and further gas outflow is prevented. Therefore, the closed space 70 is formed in a structure that does not generate a positive gas flow.

  In this embodiment, the partition plate 28 is fixed to the chamber 11 by welding. However, a slight gap exists between the partition plate 28 and the chamber 11 so that the closed space 70 is not completely sealed. Even a simple fixing method can be adopted. Even in this case, the effect of reducing the flow rate of the gas passing through the opening 27 can be obtained at a constant rate.

  Even if the partition plate 28 extending from the reaction tube 12 is not fixed to the inner wall 11c of the chamber 11 and there is a slight gap between the partition plate 28 and the chamber 11, It is only necessary that the space 70 is maintained in a substantially closed state. Similarly, the partition plate 28 may include a first part extending from the reaction tube 12 and a second part extending from the chamber 11 and fixed in contact with the first part. good. In this case, if the closed space 70 is maintained in a substantially closed state, the first portion and the second portion may be close to each other, and the first portion and the second portion It may be a structure in which the portions are located on the inner periphery and the outer periphery and overlap each other. Further, the partition plate 28 is not extended from the reaction tube 12 or the chamber 11 but may be an independent member.

  Next, a simulation performed based on the configuration of the MOCVD apparatus in FIG. 1 will be described. Here, the above-mentioned effect of preventing the generation of gas flow in the enclosed space 70 was confirmed by fluid simulation using a computer. 2 to 4 are cross-sectional views showing a simplified shape of the MOCVD apparatus in FIG. 1 in the simulation. 2 corresponds to a cross section taken along line II-II in FIG. 1, FIG. 3 corresponds to a cross section shown in FIG. 1, and FIG. 4 shows a cross section taken along line IV-IV in FIG. It corresponds to.

  2 to 4, in this simulation, the size of the space 60 in the chamber 11 is 100 mm in height, 200 mm in width, 350 mm in length, and the size of the processing space 50 in the reaction tube 12 is The height was 10 mm, the width was 150 mm, and the length was 300 mm. The opening surface of the opening 27 was a square having a size of 10 mm × 10 mm, and the cross-sectional shape of the closed space 70 formed by the partition plate 28 was a rectangular shape having a size of 80 mm × 100 mm. A gap of 1 mm was set between the partition plate 28 and the reaction tube 12.

The space 60 and the processing space 50 are filled with nitrogen gas at 1 atm (1.01325 × 10 ⁵ Pa). A gas inflow condition 31 in which 1 atm of nitrogen gas having a flow rate of 1 m / s flows is set on one end 12 m side of the reaction tube 12, and free discharge of gas is performed on the other end 12 n side of the reaction tube 12. Allowable gas outflow conditions 32 were set. On the surface of the chamber 11 and the surface of the reaction tube 12, no-slip wall conditions were set so that the gas flow velocity was zero on these surfaces.

Under these condition settings, the flow rate of the gas passing through the opening 27 from the processing space 50 (the flow rate of the gas flowing in the direction shown by the arrow 61 in FIG. 3) is changed to the implementation of the MOCVD apparatus shown in FIGS. Calculation was performed for each of the example and a comparative example in which the partition plate 28 was removed from the MOCVD apparatus shown in FIGS. As a result, in the example, the flow rate of the gas passing through the opening 27 was 541 mm ³ / s, and in the comparative example, the flow rate of the gas passing through the opening 27 was 1229 mm ³ / s. From this result, it was confirmed that by providing the partition plate 28, the flow rate of the gas passing through the opening 27 can be reduced by about 0.44 times.

  The MOCVD apparatus 10 as a semiconductor processing apparatus according to Embodiment 1 of the present invention defines a chamber 11 as a processing chamber and a processing space 50 as an internal space in which a substrate 14 as a processing object is installed. The semiconductor processing apparatus includes a reaction tube 12 disposed inside and a pyrometer 25 provided outside the reaction tube 12 as a non-contact sensor for observing the inside of the reaction tube 12. In the processing space 50, a reactive gas for processing the substrate 14 flows. An opening 27 is formed in the reaction tube 12 between the pyrometer 25 and the substrate 14. The MOCVD apparatus 10 further includes a partition plate 28 that is provided between the opening 27 and the pyrometer 25 and forms a closed space 70 that communicates with the processing space 50 through the opening 27.

  The closed space 70 is set in a viscous flow pressure region having a pressure of 1 kPa or more. In the processing space 50, the reaction gas flows substantially parallel to the growth surface 14 a as the processing surface of the substrate 14. The opening 27 is formed such that the surface where the opening 27 opens into the processing space 50 extends substantially parallel to the flow direction of the reaction gas. The partition plate 28 is provided so as to protrude from the reaction tube 12 to the side opposite to the processing space 50.

  According to the MOCVD apparatus 10 according to the first embodiment of the present invention configured as described above, by providing the partition plate 28, the gas in / out from the processing space 50 through the opening 27 is suppressed. For this reason, the gas flow in the processing space 50 is not greatly disturbed. Further, in the present embodiment, since the partition plate 28 is provided so as to protrude outside the processing space 50, the partition plate 28 does not disturb the gas flow in the processing space 50. For this reason, a desired film forming process can be performed on the growth surface 14 a of the substrate 14.

  Further, the emitted light emitted from the substrate 14 passes through the opening 27 and reaches the pyrometer 25. For this reason, even if the deposit 15 is generated on the inner wall 12c of the reaction tube 12, the progress of the radiated light is not blocked by the deposit 15, and the accurate temperature of the substrate 14 can be measured. Furthermore, by feeding back the measurement value obtained by the pyrometer 25 to the control unit of the MOCVD apparatus 10, the film growth conditions such as temperature and gas flow rate can be precisely controlled. Thereby, a high-quality film forming process can be realized.

  In the present embodiment, the cylindrical horizontal MOCVD apparatus 10 in which the cylindrical reaction tubes 12 are horizontally arranged has been described. However, the present invention is not limited to this, and the present invention is applied to, for example, a circular horizontal semiconductor processing apparatus. It can also be applied. In this circular horizontal type semiconductor processing apparatus, the reaction tube is composed of two circular plates arranged one above the other at a distance from each other. The substrate is disposed on the lower disk. The reaction gas is introduced into the space between the upper and lower disks from the vicinity of the center of the upper disk and processes the substrate while flowing in the radial direction of the disk. A plurality of partition members for guiding the reaction gas in the radial direction of the disk may be provided in the space between the upper and lower disks.

  In the present embodiment, the pyrometer 25 is provided outside the chamber 11, but the invention is not limited to this. For example, an ellipsometer for measuring the film thickness formed on the growth surface 14a of the substrate 14 is provided. Also good. Further, the invention is not limited to an optical non-contact sensor, and a non-contact sensor such as a magnetic field type or a potential difference detection type may be provided. Further, the measurement target by the non-contact sensor is not limited to the substrate 14 that is the processing target, and may be a target useful for film formation control such as the temperature of the inner wall 12c of the reaction tube 12, for example.

  1 is provided with a light source 30 as a light irradiating unit that irradiates light toward the substrate 14 that is a processing target in order to promote the reaction in the reaction tube 12 at the position where the pyrometer 25 is provided. May be.

  FIG. 5 is a cross-sectional view schematically showing a position surrounded by a two-dot chain line V in FIG. Referring to FIG. 5, in the figure, the luminous flux of the emitted light emitted from the substrate 14 is represented as an observation luminous flux 33 having a truncated cone shape. It is preferable that the opening size of the opening 27 is determined so as not to prevent the observation light beam 33 of the pyrometer 25 from proceeding.

  Assuming that the opening 27 is circular, the diameter of the opening surface of the opening 27 is set to be equal to or larger than the diameter of the observation light beam 33 in the opening 27. For example, a pyrometer 25 having a lens diameter of 5 mm and a measurement diameter of 2 mm at a measurement distance of 200 mm is installed at a position 200 mm away from the substrate 14 and the distance from the substrate 14 to the opening 27 is 20 mm. Then, the diameter of the observation light beam 33 in the opening 27 is 2.3 mm. In this case, when the diameter of the opening surface of the opening 27 is less than 2.3 mm, a part of the observation light is blocked by the reaction tube 12 that has lost its permeability due to the deposit 15. Therefore, the diameter of the opening surface of the opening 27 is set to 2.3 mm or more in order to prevent the amount of light incident on the pyrometer 25 from decreasing and the measurement accuracy from decreasing.

(Embodiment 2)
FIG. 6 is a cross-sectional view showing an MOCVD apparatus according to Embodiment 2 of the present invention. Compared with the MOCVD apparatus 10 in the first embodiment, the MOCVD apparatus in the present embodiment basically has the same structure. Hereinafter, the description of the overlapping structure will not be repeated.

  With reference to FIG. 6, in the present embodiment, a cylindrical member 29 is provided in the closed space 70. The cylindrical member 29 extends in the circumferential direction so as to surround the opening 27, and extends from the reaction tube 12 toward the chamber 11. The cylindrical member 29 is fixed to the top surface 12a of the reaction tube 12 by means such as welding. The tubular member 29 extends from the reaction tube 12 to the closed space 70 and extends to a position away from the chamber 11.

  By providing the cylindrical member 29, the pipe resistance of the gas passing through the opening 27 is increased. Thereby, since the gas flow rate which passes the opening part 27 reduces, it can suppress more effectively that disorder arises in a gas flow in the process space 50. FIG. In order to further increase the pipe resistance, the length of the cylindrical member 29 is preferably long, and the inner diameter of the cylindrical member 29 is preferably small as long as the observation light flux of the pyrometer 25 is not blocked.

  The cross-sectional shape of the cylindrical member 29 is not limited to a perfect circle, and may be a polygon or a shape including a curve. The cylindrical member 29 may have an opening cut out in a part of the circumferential direction. In this case, the cross-sectional shape of the cylindrical member is a C shape. Further, for example, if the cylindrical member 29 has a rectangular cross-sectional shape and is formed from four plate members joined by welding, a gap may be generated at a joint portion between the plate members. Also in these cases, the effect of increasing the pipe resistance of the gas passing through the opening 27 can be obtained at a certain rate.

  The method of fixing the cylindrical member 29 to the reaction tube 12 is not limited to welding, and various methods such as fastening and fitting may be used. In addition, even in a fixing method in which a slight gap may exist between the reaction tube 12 and the cylindrical member 29, the effect of increasing the pipe resistance of the gas passing through the opening 27 can be similarly obtained. it can.

  According to the MOCVD apparatus in the second embodiment of the present invention configured as described above, the same effects as those described in the first embodiment can be obtained. In addition, the entry and exit of gas from the processing space 50 is effectively suppressed, and a higher-quality film forming process can be realized.

(Embodiment 3)
FIG. 7 is a cross-sectional view showing an MOCVD apparatus according to Embodiment 3 of the present invention. Compared with the MOCVD apparatus 10 in the first embodiment, the MOCVD apparatus in the present embodiment basically has the same structure. Hereinafter, the description of the overlapping structure will not be repeated.

  Referring to FIG. 7, the MOCVD apparatus in the present embodiment is connected to blockage space 70 by being connected to pressure sensor 41 that detects the pressure in processing space 50, pressure sensor 42 that detects the pressure in blockage space 70, and blockage. A pressure adjustment mechanism 36 that adjusts the pressure in the space 70, and a controller 35 that is electrically connected to the pressure adjustment mechanism 36 and controls the pressure adjustment mechanism 36 based on the pressure values detected by the pressure sensors 41 and 42. Is further provided.

  The pressure sensor 41 and the pressure sensor 42 are disposed in the processing space 50 and the closed space 70, respectively. The pressure adjustment mechanism 36 includes a stretchable portion 37 that can be stretched in a predetermined direction, and a movable portion 38 that is provided in the stretchable portion 37 and forms a space 80 that communicates with the closed space 70 together with the stretchable portion 37. The movable part 38 is provided so as to be movable in the direction in which the expansion / contraction part 37 expands / contracts.

  The control unit 35 receives the output pressure value P1 of the pressure sensor 41 and the output pressure value P2 of the pressure sensor 42. The control unit 35 compares the output pressure value P1 and the output pressure value P2, and if P1> P2, sends a signal to the movable unit 38 so as to move in the direction in which the volume V of the space 80 is reduced. In the case of <P2, a signal is sent to the movable unit 38 so as to move in the direction in which the volume V of the space 80 is enlarged. As a result, the pressure adjustment mechanism 36 is controlled so that there is no constant pressure difference between the processing space 50 and the closed space 70.

  FIG. 8 is a sectional view showing a first modification of the MOCVD apparatus in FIG. Referring to FIG. 8, in this modification, the pressure adjustment mechanism 36 includes a container 45 that forms a space 90 communicating with the closed space 70, and an inert gas introduction pipe 46 and an inert gas discharge pipe 47. 45, and an inert gas intake / exhaust portion 44 that adjusts the pressure P3 of the space 90. The inert gas intake / exhaust unit 44 is electrically connected to a control unit 35 that controls the inert gas intake / exhaust unit 44.

  The control unit 35 compares the output pressure value P1 and the output pressure value P2, and when P1> P2, the inert gas intake / exhaust gas is supplied so as to supply the inert gas to the space 90 through the inert gas introduction pipe 46. A signal is sent to the unit 44. Thereby, the pressure P3 of the space 90 is increased. When P1 <P2, the control unit 35 sends a signal to the inert gas intake / exhaust unit 44 so as to suck the inert gas from the space 90 through the inert gas discharge pipe 47. Thereby, the pressure P3 of the space 90 is decreased. As a result, the pressure adjustment mechanism 36 is controlled so that there is no constant pressure difference between the processing space 50 and the closed space 70.

  FIG. 9 is a cross-sectional view showing a second modification of the MOCVD apparatus in FIG. Referring to FIG. 9, in the present modification, the MOCVD apparatus includes two pressure adjusting mechanisms 36a and 36b. The pressure adjustment mechanism 36 a includes a container 52 that forms a space 95 that communicates with the closed space 70, and an adjustment valve 53 that is installed on a conduit that connects the closed space 70 and the space 95. Similarly, the pressure adjustment mechanism 36 b includes a container 54 that forms a space 96 that communicates with the closed space 70, and an adjustment valve 55 that is installed on a pipe line that connects the closed space 70 and the space 96.

  The pressure P3a in the space 95 is set to a value slightly lower than the lowest pressure in the predicted fluctuation of the pressure P1. The pressure P3b in the space 96 is set to a value slightly higher than the lowest pressure within the fluctuation of the predicted pressure P1. The adjustment valves 53 and 55 are electrically connected to the control unit 35.

  The regulating valves 53 and 55 are normally kept closed. The control unit 35 compares the output pressure value P1 and the output pressure value P2, and if P1> P2, sends a signal to open the adjustment valve 55. As a result, the inert gas in the space 96 flows into the closed space 70 and the pressure P2 increases. In the case of P1 <P2, the control unit 35 transmits a signal so as to open the adjustment valve 53. Thereby, the gas in the closed space 70 is sucked into the space 95, and the pressure P2 becomes low. As a result, the pressure adjusting mechanisms 36a and 36b are controlled so that there is always a pressure difference between the processing space 50 and the closed space 70.

  According to the MOCVD apparatus in the third embodiment of the present invention configured as described above, the same effects as those described in the first embodiment can be obtained. In addition, the entry and exit of gas from the processing space 50 is effectively suppressed, and a higher-quality film forming process can be realized.

  Note that another MOCVD apparatus may be configured by appropriately combining the structures of the MOCVD apparatuses in Embodiments 1 to 3 described above.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is sectional drawing which shows the MOCVD apparatus in Embodiment 1 of this invention. FIG. 2 is a cross-sectional view showing a simplified shape of the MOCVD apparatus in FIG. 1 in a simulation, and is a view corresponding to a cross section along the line II-II in FIG. 1. FIG. 2 is a cross-sectional view showing a simplified shape of the MOCVD apparatus in FIG. 1 in a simulation, and corresponds to the cross section shown in FIG. 1. In simulation, it is sectional drawing which shows the shape which simplified the MOCVD apparatus in FIG. 1, and is a figure equivalent to the cross section along the IV-IV line in FIG. It is sectional drawing which represented typically the position enclosed with the dashed-two dotted line V in FIG. It is sectional drawing which shows the MOCVD apparatus in Embodiment 2 of this invention. It is sectional drawing which shows the MOCVD apparatus in Embodiment 3 of this invention. It is sectional drawing which shows the 1st modification of the MOCVD apparatus in FIG. It is sectional drawing which shows the 2nd modification of the MOCVD apparatus in FIG. It is sectional drawing which shows the conventional vapor phase growth apparatus. It is sectional drawing which shows the molecular beam epitaxial growth apparatus disclosed by Unexamined-Japanese-Patent No. 61-163632. It is sectional drawing which shows the example of improvement of the vapor phase growth apparatus in FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 MOCVD apparatus, 11 chamber, 12 reaction tube, 14 substrate, 20 material gas introduction tube, 21 material gas discharge tube, 22 material gas supply device, 25 pyrometer, 27 opening part, 28 partition plate, 29 cylindrical member, 30 light source , 33 Observation luminous flux, 36, 36a, 36b Pressure adjusting mechanism, 41, 42 Pressure sensor, 50 processing space, 70 closed space.

Claims (7)

A processing chamber;
Defining an internal space in which the object to be treated is installed, and a reaction tube disposed in the processing chamber;
A non-contact sensor provided outside the reaction tube and observing the inside of the reaction tube;
In the internal space, a reaction gas for processing the processing object flows,
In the reaction tube, an opening is formed between the non-contact sensor and the processing object, and further,
A semiconductor processing apparatus, comprising: a partition member that is provided between the opening and the non-contact sensor and forms a substantially closed space that communicates with the internal space through the opening. The reaction tube has a supply port through which a reaction gas is supplied to the internal space, and a discharge port through which the reaction gas is discharged from the internal space,
The semiconductor processing apparatus according to claim 1, wherein the processing object is disposed between the supply port and the discharge port. An observation medium for observing the processing object is emitted in a bundle from the processing object toward the non-contact sensor,
3. The semiconductor processing apparatus according to claim 1, wherein the opening has an opening width equal to or larger than a cross-sectional area of the bundle of observation media on an opening surface of the opening.   4. The semiconductor according to claim 1, further comprising a substantially cylindrical member that is disposed in the substantially enclosed space, surrounds the opening, and extends from the opening to a side opposite to the internal space. 5. Processing equipment. A first pressure detector for detecting the pressure in the internal space;
A second pressure detector for detecting the pressure in the substantially enclosed space;
A pressure adjusting unit that adjusts the pressure of the substantially enclosed space;
The pressure adjusting unit reduces a pressure difference between the internal space and the substantially enclosed space based on pressure values of the internal space and the substantially enclosed space respectively detected by the first and second pressure detection units. The semiconductor processing apparatus of any one of Claim 1 to 4 which adjusts the pressure of the said substantially enclosed space as follows. A semiconductor processing method using the semiconductor processing apparatus according to claim 1,
A semiconductor processing method, wherein the processing object is observed by the non-contact sensor. A processing chamber;
Defining an internal space in which the object to be treated is installed, and a reaction tube disposed in the processing chamber;
A semiconductor processing apparatus provided with a light irradiation unit that is provided outside the reaction tube and irradiates light toward the processing object;
In the internal space, a reaction gas for processing the processing object flows,
In the reaction tube, an opening is formed between the light irradiation unit and the processing object, and
A semiconductor processing apparatus, comprising: a partition member provided between the opening and the light irradiation unit and forming a substantially closed space communicating with the internal space through the opening.

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