Temperature distribution evaluation method, temperature distribution evaluation device, and evaluation method for soaking range

Abstract

An object of the present invention is to provide a novel temperature distribution evaluation method, a temperature distribution evaluation device, and a soaking range evaluation method. The temperature distribution evaluation method evaluates the temperature distribution of a heating region (40A) provided in a heating device (40), wherein in the heating region (40A), a semiconductor substrate (10) and a transceiver (20) for mutually transporting raw materials with the semiconductor substrate (10) are heated, and the temperature distribution of the heating region (40A) is evaluated based on a substrate thickness change amount (A) of the semiconductor substrate (10). Thereby, it is possible to evaluate the temperature distribution in a high temperature region such as 1600 to 2200 °C, which is difficult to achieve due to material limitations of thermocouples.

Description

Technical Field

[0001] The present invention relates to a temperature distribution evaluation method, a temperature distribution evaluation apparatus, and a soaking range evaluation method. Background Art

[0002] Improvement in the yield of semiconductor device manufacturing is achieved by temperature management in a heating environment in a semiconductor process. Temperature management is important, for example, in a crystal growth process, an impurity introduction process, an annealing process, an etching process, and the like.

[0003] For example, a SiC (silicon carbide) material is expected as a suitable power device material having a higher dielectric breakdown electric field strength and thermal conductivity than a Si (silicon) material or the like. However, due to its thermal stability, the SiC material needs to be heated in a higher temperature range than a Si material or the like. Not limited to the SiC material, it is sometimes difficult to perform temperature management for a semiconductor material having a higher melting point than a Si material as compared with a conventional Si semiconductor process.

[0004] Patent Document 1 discloses a heating furnace temperature evaluation jig that can measure a temperature of 1600°C to 1800°C by forming a recess in a SiC substrate, disposing a thermocouple in the recess, and fixing it using a filling member having a heat-resistant adhesive member.

[0005] Prior Art Documents

[0006] Patent Documents

[0007] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2016-8821 Summary of the Invention

[0008] Problems to be Solved by the Invention

[0009] In the case of using the heating furnace temperature evaluation jig described in Patent Document 1, it is necessary to route a thermocouple wire bundle from outside the heating area. Therefore, there is a problem that it is difficult to evaluate the temperature distribution in the heating area because the temperature escapes from the routing part. In addition, due to the material limitation of the thermocouple, it is difficult to evaluate the temperature distribution in a high temperature range of 1600 to 2200°C or the like.

[0010] The technical problem to be solved by the present invention is to provide a novel temperature distribution evaluation method, a temperature distribution evaluation apparatus, and a soaking range evaluation method.

[0011] Means for Solving the Problems

[0012] The present invention for solving the above problems is a method for evaluating a temperature distribution, which evaluates the temperature distribution in a heating region of a heating device, wherein in the heating region, a semiconductor substrate and a transceiver for mutually transporting raw materials with the semiconductor substrate are heated, and the temperature distribution in the heating region is evaluated based on the change amount of the substrate thickness of the semiconductor substrate.

[0013] Thus, by evaluating the temperature distribution in the heating region based on the change amount of the substrate thickness of the semiconductor substrate, it is possible to evaluate the temperature distribution in a temperature region higher than that of a thermocouple without performing wiring.

[0014] In a preferred embodiment of the present invention, the semiconductor substrate and the transceiver are relatively arranged, and heating is performed so as to form a temperature gradient between the semiconductor substrate and the transceiver.

[0015] In addition, in a preferred embodiment of the present invention, the change amount of the substrate thickness is an amount that changes by using the temperature gradient formed in the heating region as a driving force.

[0016] Thus, by using the temperature gradient as the driving force for the change amount of the substrate thickness, the temperature distribution in the heating region can be evaluated with high accuracy.

[0017] In a preferred embodiment of the present invention, it includes: a measurement point setting step of setting a plurality of measurement points in the heating region; a substrate arrangement step of arranging the semiconductor substrate and the transceiver at positions corresponding to the measurement points; a change amount measurement step of measuring the change amount of the substrate thickness of the semiconductor substrate corresponding to the measurement points; and a change amount comparison step of comparing the plurality of change amounts of the substrate thickness.

[0018] In a preferred embodiment of the present invention, the measurement point setting step sets a plurality of the measurement points in the horizontal direction of the heating region.

[0019] By setting measurement points in such a direction, the temperature distribution in the horizontal direction of the heating region can be measured.

[0020] In a preferred embodiment of the present invention, the measurement point setting step sets a plurality of the measurement points in the height direction of the heating region.

[0021] By setting measurement points in such a direction, the temperature distribution in the height direction of the heating region can be measured.

[0022] In a preferred embodiment of the present invention, the substrate arrangement step arranges a plurality of the semiconductor substrates along the measurement points.

[0023] Thus, by arranging a plurality of semiconductor substrates along the measurement points, the semiconductor substrates can be arranged at the positions required for temperature distribution measurement. That is, there is no need to use a semiconductor substrate that covers the entire area of the heating region.

[0024] In a preferred embodiment of the present invention, the substrate thickness change amount is an etching amount or a growth amount.

[0025] In this way, the temperature distribution can be evaluated based on the etching amount and the growth amount. Therefore, a change amount that is easy to measure can be appropriately selected to evaluate the temperature distribution.

[0026] In a preferred embodiment of the present invention, the semiconductor substrate and the transceiver are selected from any of the materials SiC, GaN, and AlN.

[0027] By selecting a semiconductor substrate and a transceiver of such materials, the temperature distribution in a temperature region that is difficult to measure with a thermocouple can be measured. In addition, by selecting the optimal semiconductor material according to the temperature region to be measured, the temperature distribution can be evaluated with higher accuracy.

[0028] The present invention also relates to a temperature distribution evaluation device, comprising: a temperature distribution evaluation unit disposed within a heating region of a heating device, wherein the temperature distribution evaluation unit has: a semiconductor substrate; and a transceiver that conveys raw materials to each other by heating while facing the semiconductor substrate.

[0029] By using such a temperature distribution evaluation device, temperature distribution evaluation can be performed in a temperature region higher than that of a thermocouple without wiring.

[0030] In a preferred embodiment of the present invention, the temperature distribution evaluation unit has: a setting tool for relatively arranging the semiconductor substrate and the transceiver.

[0031] In this way, by having a setting tool for relatively arranging the semiconductor substrate and the transceiver, the distance between the semiconductor substrate and the transceiver can be adjusted with high precision.

[0032] In a preferred embodiment of the present invention, a plurality of the temperature distribution evaluation units are provided.

[0033] In this way, by providing a plurality of temperature distribution evaluation units, there is no need to use a semiconductor substrate that covers the entire area of the heating region.

[0034] In a preferred embodiment of the present invention, the setting tool is provided with: a first abutting surface that abuts against the semiconductor substrate; and a second abutting surface that abuts against the transceiver.

[0035] In this way, by having a contact surface that contacts the semiconductor substrate and the transceiver, a quasi-closed space can be formed between the semiconductor substrate and the transceiver, and the temperature distribution evaluation can be performed with higher accuracy.

[0036] In a preferred embodiment of the present invention, there is provided: a positioning unit for positioning the semiconductor substrate and / or the transceiver.

[0037] In this way, by providing a positioning unit for the semiconductor substrate, accidental deviation of the semiconductor substrate or the transceiver can be suppressed.

[0038] In a preferred embodiment of the present invention, the positioning unit is a frame portion provided along the edge of the semiconductor substrate and / or the transceiver.

[0039] In this way, by providing the frame portion, positioning can be easily performed.

[0040] In a preferred embodiment of the present invention, it further includes: a storage container for storing the temperature distribution evaluation unit, and the storage container forms an atmosphere containing the elements constituting the semiconductor substrate inside the container when heated.

[0041] In this way, by providing a storage container for storing the temperature distribution evaluation unit, exhaust of raw materials from the quasi-closed space can be suppressed.

[0042] In a preferred embodiment of the present invention, it further includes: a storage container for storing the semiconductor substrate, and a part of the storage container is constituted by the transceiver.

[0043] In this way, by constituting a part of the storage container with the transceiver, atomic migration with the semiconductor substrate can be performed while forming a quasi-closed space.

[0044] In a preferred embodiment of the present invention, the semiconductor substrate and the transceiver are selected from any of the materials SiC, GaN, and AlN.

[0045] In addition, the present invention also relates to a method for evaluating the isothermal range. That is, the method for evaluating the isothermal range according to one embodiment of the present invention heats a semiconductor substrate and a transceiver that mutually transfer raw materials with the semiconductor substrate at a plurality of measurement points in the heating region of a heating device, and evaluates the isothermal range of the heating region based on the change amount of the substrate thickness of the semiconductor substrate.

[0046] In a preferred embodiment of the present invention, the semiconductor substrate and the transceiver are disposed opposite to each other, and heating is performed so as to form a temperature gradient between the semiconductor substrate and the transceiver.

[0047] In a preferred embodiment of the present invention, it includes: a measurement point setting step of setting a plurality of measurement points within the heating region; a substrate arrangement step of arranging the semiconductor substrate and the transceiver at positions corresponding to the measurement points; a heating step of heating the semiconductor substrate and the transceiver in the heating region to cause a change in the substrate thickness of the semiconductor substrate; a change amount measurement step of measuring the change amount of the substrate thickness of the semiconductor substrate corresponding to the measurement points; and a change amount comparison step of comparing the change amounts of the substrate thickness at the plurality of measurement points.

[0048] In a preferred embodiment of the present invention, the heating temperature of the semiconductor substrate and the transceiver is 1600 °C or higher.

[0049] In a preferred embodiment of the present invention, the heating temperature of the semiconductor substrate and the transceiver is 1800 °C or higher.

[0050] Effects of the Invention

[0051] According to the disclosed technology, a novel temperature distribution evaluation method, a temperature distribution evaluation device, and a method for evaluating a heat dissipation range can be provided.

[0052] Other technical problems to be solved, features, and advantages will become apparent by reading the following detailed embodiments in conjunction with the drawings and claims. Description of the Drawings

[0053] Figure 1 It is a schematic diagram illustrating the temperature distribution evaluation step of the temperature distribution evaluation method according to the present invention.

[0054] Figure 2 It is a schematic diagram illustrating the measurement point setting step of the temperature distribution evaluation method according to the present invention.

[0055] Figure 3 It is a schematic diagram illustrating the steps from the substrate arrangement step to the change amount comparison step of the temperature distribution evaluation method according to the present invention.

[0056] Figure 4 It is an explanatory diagram of the temperature distribution measurement device according to Embodiment 1.

[0057] Figure 5 It is an explanatory diagram of the temperature distribution measurement device according to Embodiment 1.

[0058] Figure 6 It is an explanatory diagram of the temperature distribution measurement device according to Embodiment 1.

[0059] Figure 7 It is an explanatory diagram of the temperature distribution measurement device according to Embodiment 2.

[0060] Figure 8 It is a graph showing the distance dependence of the transfer source and the transfer destination when showing the substrate thickness change rate in the reference example.

[0061] Figure 9 It is a graph showing the position dependence of the substrate thickness change rate in the embodiment, etc. Detailed Description of the Invention

[0062] Hereinafter, the preferred embodiments of the illustrated invention will be described in detail with reference to the accompanying drawings.

[0063] The technical scope of the present invention is not limited to the embodiments shown in the drawings, and can be appropriately changed within the scope described in the claims.

[0064] "Temperature Distribution Evaluation Method"

[0065] The present invention is a temperature distribution evaluation method for evaluating the temperature distribution of the heating region 40A included in the heating device 40, and has: a temperature distribution evaluation step S1, in which the semiconductor substrate 10 and the transceiver 20 that mutually transfer raw materials with the semiconductor substrate 10 are heated in the heating region 40A, and the temperature distribution of the heating region 40A is evaluated based on the substrate thickness change amount A of the semiconductor substrate 10.

[0066] Specifically, as Figure 1 shown, the temperature distribution evaluation step S1 includes: a measurement point setting step S10, in which a plurality of measurement points P are set in the heating region 40A; a substrate arrangement step S20, in which the semiconductor substrate 10 and the transceiver 20 are arranged at positions corresponding to the measurement points P; a heating step S30, in which the substrate thickness T is changed by heating the semiconductor substrate 10 and the transceiver 20 in the heating region 40A; a change amount measurement step S40, in which the substrate thickness change amount A of the semiconductor substrate 10 corresponding to the measurement point P is measured; and a change amount comparison step S50, in which the substrate thickness change amounts A at the plurality of measurement points P are compared.

[0067] Hereinafter, with reference to Figure 2 and Figure 3 the temperature distribution evaluation step S1 will be described in detail.

[0068] <Measurement Point Setting Step S10>

[0069] The measurement point setting step S10 is a step of setting a plurality of measurement points P in the heating region 40A.

[0070] First, the heating device 40, which is the measurement object of the temperature distribution of the present invention, will be described.

[0071] Figure 2This is an example of the heating device 40 which is the object of measurement in the temperature distribution evaluation method according to the present invention. In addition, any device having a heating region 40A for the purpose of heat-treating an object can be the object of measurement in the present invention.

[0072] The heating device 40 includes: a heating chamber 41 in which a heating region 40A for heating a heat-treatment object is formed; a stage 42 capable of placing the heat-treatment object in the heating region 40A; a heater 43 for forming the heating region 40A; a vacuum forming valve 44 for evacuating the heating chamber 41; and an inert gas injection valve 45 for introducing an inert gas into the heating chamber 41.

[0073] The heating device 40 is configured to heat-treat an object in a temperature range of 1000°C to 2300°C. In addition, it is configured to heat-treat an object preferably at 1600°C or higher, more preferably at 1800°C or higher, and further preferably at 2000°C or higher.

[0074] A temperature gradient is formed in the heating chamber 41 (heating region 40A) during heat treatment. This temperature gradient is formed, for example, by releasing a small amount of heat from the contact portion between the stage 42 and the heating chamber 41. In this case, the temperature gradient can be set such that the temperature decreases from the upper side to the lower side of the heating chamber 41 to heat-treat the object.

[0075] In addition, a structure in which a temperature gradient is formed by the heater 43 can also be adopted. For example, the heater 43 can be configured to have a plurality of heaters arranged on the upper side. In addition, the heater 43 can be configured to have a larger width as it goes upward. Alternatively, the heater 43 can be configured to increase the supplied power as it goes upward.

[0076] Moreover, the temperature gradient can be set such that the temperature decreases from the lower side to the upper side.

[0077] The measurement point P can be set at any position within the heating region 40A.

[0078] Figure 2 (a) in shows a side view when a plurality of measurement points P are set in the horizontal direction of the heating region 40A. Figure 2 (b) in shows a top view when a plurality of measurement points P are set in the horizontal direction of the heating region 40A.

[0079] In addition, of course, a plurality of measurement points P can also be set in the height direction of the heating region 40A.

[0080] <Substrate placement step S20>

[0081] The substrate arrangement step S20 is a step of arranging the semiconductor substrate 10 and the transceiver 20 along the plurality of measurement points P set in the measurement point setting step S10 .

[0082] Figure 3 Shown along Figure 2 The measurement points P1 and P2 are arranged to measure the conditions of the semiconductor substrate 10 and the transceiver 20. Specifically, the semiconductor substrate 10 and the transceiver 20 are arranged along the direction in which the plurality of measurement points P are arranged, and are arranged so that the plurality of measurement points P and the surface of the semiconductor substrate 10 where the substrate thickness changes are approximately parallel. Therefore, the measurement point P may also be located on the surface of the semiconductor substrate 10, or the measurement point P may also be located at a position at a certain distance from the surface of the semiconductor substrate 10.

[0083] The semiconductor substrate 10 may be a semiconductor wafer formed by slicing a disk from an ingot produced by a sublimation method or a single crystal substrate obtained by processing a single crystal into a thin plate. Any polymorphic form of the single crystal may be used.

[0084] Furthermore, as the material of the semiconductor substrate 10 , a SiC substrate, a GaN substrate, and an AlN substrate can be exemplified.

[0085] The transceiver 20 is made of a material that transfers raw materials to and from the semiconductor substrate 10 when heated, and is preferably made of the same material as the semiconductor substrate 10. For example, when the semiconductor substrate 10 is made of single crystal SiC, the transceiver 20 is made of single crystal SiC or polycrystalline SiC. That is, the semiconductor substrate 10 may also be used as the transceiver 20.

[0086] exist Figure 3 2 shows a method of growing the semiconductor substrate 10 by placing the semiconductor substrate 10 on the low temperature side and placing the transceiver 20 on the high temperature side with respect to the temperature gradient formed by the heating device 40, but the configuration may be the opposite. That is, the semiconductor substrate 10 may be etched by placing the semiconductor substrate 10 on the high temperature side and placing the transceiver 20 on the low temperature side with respect to the temperature gradient formed by the heating device 40.

[0087] Preferably, the semiconductor substrate 10 and the transmitting and receiving body 20 are disposed in a storage container 30 forming a quasi-enclosed space. In this specification, the "quasi-enclosed space" refers to a space that can seal at least a part of the vapor generated in the container while the container can be evacuated.

[0088] By receiving or migrating the raw material (atoms) in such a quasi-enclosed space, it is possible to suppress exhaust of the raw material and more accurately measure the substrate thickness variation A. That is, it is preferable that the storage container 30 forms an atmosphere containing elements constituting the semiconductor substrate 10 in the container when heated.

[0089] Preferably, the storage container 30 is made of a high melting point material having a melting point equal to or higher than that of the semiconductor substrate 10. Specifically, examples include: C as a general heat-resistant component, W, Re, Os, Ta, Mo as high melting point metals, Ta9C8, HfC, TaC, NbC, ZrC, Ta2C, TiC, WC, MoC as carbides, HfN, TaN, BN, Ta2N, ZrN, TiN as nitrides, HfB2, TaB2, ZrB2, NB2, TiB2 as borides, or the same material as the semiconductor substrate 10, i.e., SiC, GaN, AIN, etc.

[0090] When the storage container 30 is made of the same material as the semiconductor substrate 10, an atmosphere of the elements constituting the semiconductor substrate 10 can be formed inside the container during heating. In addition, a vapor source for supplying vapor of the same elements as the semiconductor substrate 10 can also be arranged inside the storage container 30.

[0091] In addition, whether to use the storage container 30 can be selected according to the structure of the heating device 40. That is, when the heating region 40A of the heating device 40 is a structure capable of forming a quasi-closed space, the semiconductor substrate 10 and the transceiver 20 can be arranged without using the storage container 30. On the other hand, when the heating region 40A of the heating device 40 is an open system, it is preferable to use the storage container 30.

[0092] <Heating step S30>

[0093] As Figure 3 shown, the heating step S30 is a step of heating to form a temperature gradient between the semiconductor substrate 10 and the transceiver 20 arranged in the substrate arrangement step S20. In this way, by setting a temperature gradient between the semiconductor substrate 10 and the transceiver 20 and heating, atomic transport is carried out with the temperature gradient as the driving force, and etching or growth of the semiconductor substrate 10 is performed.

[0094] At this time, when the temperature is different according to the measurement point P, growth or etching of the semiconductor substrate 10 is performed to reflect the temperature of each measurement point P. That is, if it is a high-temperature part within the heating region 40A, the etching amount E and the growth amount G of the semiconductor substrate 10 and the transceiver 20 become larger, while in the low-temperature part of the heating region 40A, the etching amount E and the growth amount G become smaller.

[0095] In Figure 3 it, the etching amount E1 and the growth amount G1 of the measurement point P1 as the high-temperature part become larger, and the etching amount E2 and the growth amount G2 of the measurement point P2 as the low-temperature part become smaller.

[0096] <Substrate Thickness Variation Measurement Step S40>

[0097] The substrate thickness variation measurement step S40 is a step of measuring the substrate thickness variation ΔA of the semiconductor substrate 10 that changes in the heating step S30. The substrate thickness variation ΔA can be obtained from the substrate thickness before the heating step S30 and the substrate thickness after the heating step S30. In addition, the substrate thickness variation ΔA includes an etching amount E and a growth amount G.

[0098] As a measurement means, a measurement method including an electron microscope, a laser microscope, a probe microscope, etc. can be adopted without particular limitation. For example, by breaking the semiconductor substrate 10 at the measurement point P after the heating step S30 and observing the fracture surface using an electron microscope, the growth amount G at the measurement point P can be measured.

[0099] In addition, a growth layer with different contrasts in the electron microscope image can be formed on the semiconductor substrate 10 in advance, and the etching amount E and the growth amount G can be measured based on the amount of the growth layer observed after the heating step S30.

[0100] <Substrate Thickness Variation Comparison Step S50>

[0101] The substrate thickness variation comparison step S50 is a step of comparing the substrate thickness variations ΔA at the respective measurement points P measured in the substrate thickness variation measurement step S40 for each measurement point P. For example, when comparing Figure 3 the substrate thickness variations ΔA (growth amount G) of the measurement point P1 and the measurement point P2, the growth amount G1 of the measurement point P1 is larger than the growth amount G2 of the measurement point P2. In addition, when using the semiconductor substrate 10 as the transceiver 20 to compare the substrate thickness variations ΔA (etching amount E), the etching amount E1 of the measurement point P1 is smaller than the etching amount E2 of the measurement point P2.

[0102] As can be seen from the above, the temperatures at the measurement points P1 and P2 in the heating region 40A are different. In addition, it can be seen that the temperature of the measurement point P2 is lower than that of the measurement point P1.

[0103] On the other hand, it can be seen that according to the measurement point P, if the substrate thickness variations ΔA (etching amount E and / or growth amount G) are substantially the same, the heating environments at these measurement points P are the same.

[0104] That is, according to the temperature distribution measurement method of the present invention, by measuring the substrate thickness variation ΔA at the measurement point P in the heating region 40A of the heating device 40, the isothermal range of the heating region 40A in a high-temperature environment of 1600 °C or above or 1800 °C or above can be grasped. Thereby, it can contribute to temperature management in the semiconductor manufacturing process and improve the yield of semiconductor device manufacturing.

[0105] "Temperature Distribution Evaluation Device"

[0106] Next, the form of the temperature evaluation device for performing the above temperature distribution evaluation will be described in detail with reference to Embodiment 1 and Embodiment 2.

[0107] <Embodiment 1>

[0108] Hereinafter, the temperature distribution evaluation device according to Embodiment 1 of the present invention will be described in detail. In addition, in this embodiment, structural elements that are substantially the same as those shown in the above temperature distribution evaluation method are denoted by the same reference numerals and their descriptions are simplified.

[0109] The temperature distribution evaluation device according to Embodiment 1 includes a temperature distribution evaluation unit U disposed in the heating region 40A of the heating device 40. As Figure 4 shown, the temperature distribution evaluation unit U has: a semiconductor substrate 10; a transceiver 20 that conveys raw materials to each other by heating while facing the semiconductor substrate 10; and a setting tool 50 that relatively arranges the semiconductor substrate 10 and the transceiver 20.

[0110] In addition, when the heating region 40A of the heating device 40 is not a quasi-closed space, a storage container 30 for storing the temperature distribution evaluation unit U is further included.

[0111] The storage container 30 is a fitting container including an upper container 31 and a lower container 32 that can be fitted to each other. A minute gap 33 is formed at the fitting portion of the upper container 31 and the lower container 32 so that the inside of the storage container 30 can be evacuated (vacuumed). Thus, it is configured to be able to form a quasi-closed space inside the storage container 30.

[0112] In addition, the storage container 30 is configured to be able to form a material environment that can form an atmosphere containing Si vapor during heating. For example, the upper container 31 and the lower container 32 are made of a high melting point material, TaC, and a structure in which a tantalum silicide layer is formed on the inner side of the container is adopted. With such a configuration, Si vapor is generated from the tantalum silicide layer during heating, and the inside of the storage container 30 can be made into a Si vapor pressure space. In addition, a storage container 30 made of polycrystalline SiC that supplies Si vapor and C vapor during heating can also be adopted.

[0113] In the present embodiment, the semiconductor substrate 10 and the transceiver 20 are described in detail using a single crystal SiC substrate, but an AlN substrate or a GaN substrate can also be used according to the temperature region to be measured.

[0114] As the semiconductor substrate 10 and the transceiver body 20, a SiC wafer obtained by cutting a ingot manufactured by a sublimation method or the like into a disc shape, or a SiC substrate obtained by processing a SiC single crystal into a thin plate shape can be exemplified. In addition, as the crystal polymorph of the SiC single crystal, any polymorph can be adopted.

[0115] In addition, a single crystal substrate or a polycrystalline substrate can be exemplified. In addition, the single crystal substrate may also have an epitaxial growth layer on its surface. In addition, the epitaxial growth layer may also be a material different from that of the single crystal substrate.

[0116] The setting tool 50 has: a support portion 51 that forms a gap H51 between the semiconductor substrate 10 and the transceiver body 20; a first abutting surface 52 that abuts against the semiconductor substrate 10; a second abutting surface 53 that abuts against the transceiver body 20; and a frame portion 54 (positioning unit) that is provided along the edges of the semiconductor substrate 10 and the transceiver body 20.

[0117] The gap H51 formed by the support portion 51 is preferably 100 mm or less, more preferably 50 mm or less, more preferably 20 mm or less, more preferably 10 mm or less, further preferably 7 mm or less, further preferably 5 mm or less, further preferably 3.5 mm or less, further preferably 3 mm or less, further preferably 2.7 mm or less. The gap H201 of the setting tool is preferably 0.7 mm or more, more preferably 1.0 mm or more, more preferably 1.2 mm or more, further preferably 1.5 mm or more, further preferably 1.7 mm or more. The gap H51 is the distance between substrates and is the distance between the transport source and the transport destination related to the raw material transport described later.

[0118] The first abutting surface 52 and the second abutting surface 53 are formed to be able to abut against the outer edge portions of the semiconductor substrate 10 and the transceiver body 20, and are set to have a size that forms a quasi-closed space in the gap H51. Therefore, the first abutting surface 52 and the second abutting surface 53 are configured to have through holes provided inside.

[0119] The frame portion 54 is provided along the edge (outer shape) of the semiconductor substrate 10 and / or the transceiver body 20 and is a positioning unit that suppresses the deviation of the semiconductor substrate 10 or the transceiver body 20 from the first abutting surface and the second abutting surface. In Figure 4 An example in which the frame portion 54 is provided at the entire peripheral portion of the setting tool 50 is shown, but a convex portion may also be provided at a part to form a positioning unit. In addition, a form in which a positioning unit is formed on one surface of the setting tool 50 may also be adopted.

[0120] In addition, the height 54H of the frame portion 54 is preferably equal to or less than the thickness of the semiconductor substrate 10 or the transceiver 20. Thus, by setting the height 54H to be equal to or less than the thickness of the semiconductor substrate 10 or the transceiver 20, close contact can be achieved with the semiconductor substrate 10 or the transceiver 20 disposed below the setting tool 50.

[0121] In addition, the length of the setting tool 50 may be exemplified as 4.0 mm, and the width may be exemplified as 8.0 mm. The width of the through hole in the setting tool 50 is, for example, 2.0 mm.

[0122] Preferably, the material of the setting tool 50 has the same structural elements as the semiconductor substrate 10 and the transceiver 20.

[0123] Next, with reference to Figure 5 and Figure 6 the steps of measuring the temperature distribution using the temperature distribution measuring device according to Embodiment 1 will be described in detail.

[0124] The temperature distribution evaluation method in Embodiment 1 includes: a measurement point setting step S10 (not shown) of setting a plurality of measurement points P in the heating region 40A; a substrate arrangement step S20 of arranging a temperature distribution evaluation unit U composed of two semiconductor substrates 10 and a setting tool 50 for oppositely arranging the semiconductor substrates 10 at a position corresponding to the measurement point P; a heating step S30 of heating the temperature distribution evaluation unit U after the substrate arrangement step S20; a change amount measurement step S40 of measuring the substrate thickness change amount A (etching amount E and / or growth amount G) of the semiconductor substrate 10 after the heating step S30; and a change amount comparison step S50 of comparing the substrate thickness change amounts A at a plurality of measurement points P.

[0125] As Figure 6 shown, the measurement point setting step S10 according to Embodiment 1 sets a plurality of measurement points P in the horizontal direction D1 of the heating region 40A. In addition, the measurement point P may be set to be arranged in the vertical direction D2 in the heating region 40A, or may be set to be arranged in the horizontal direction D1 and / or the vertical direction D2.

[0126] The heating step S30 according to Embodiment 1 can be understood to include: a raw material transfer step of transferring a raw material from one semiconductor substrate 10 to the other semiconductor substrate 10.

[0127] As Figure 5 shown, in Embodiment 1, when the temperature distribution evaluation unit U is heated, the sublimation gas is transferred from the semiconductor substrate 10 to the raw material transfer space Y. In addition, the sublimation gas and the raw material in this specification are synonymous.

[0128] The generation and transportation of the sublimated gas can be understood to proceed continuously through 1) to 5) shown below.

[0129] 1) SiC(s) → Si(v) + C(s)

[0130] 2) 2C(s) + Si(v) → SiC2(v)

[0131] 3) C(s) + 2Si(v) → Si2C(v)

[0132] 4) Si(v) + SiC2(v) → 2SiC(s)

[0133] 5) Si2C(v) → Si(v) + SiC(s)

[0134] Explanation of 1): By heating a semiconductor substrate 10 (SiC(s)), Si atoms (Si(v)) are preferentially detached (Si atom sublimation step).

[0135] Explanation of 2) and 3): C (C(s)) remaining on the surface of the semiconductor substrate 10 due to the detachment of Si atoms (Si(v)) reacts with Si vapor (Si(v)) in the raw material transportation space Y and sublimes in the raw material transportation space Y as Si2C or SiC2, etc. (C atom sublimation step).

[0136] Explanation of 4) and 5): The sublimated Si2C or SiC2, etc. reaches / diffuses to the platform on the surface of another semiconductor substrate 10 due to the temperature gradient and reaches the step, thereby continuing the polymorphism on the surface of the semiconductor substrate 10 to grow / form the growth layer (step flow growth).

[0137] The heating step includes: an Si atom sublimation step of thermally sublimating Si atoms from the semiconductor substrate 10; and a C atom sublimation step of sublimating C atoms remaining at the semiconductor substrate 10 by bonding with Si atoms in the raw material transportation space Y.

[0138] The heating step includes: an etching step of etching the surface of the semiconductor substrate as the raw material transportation source based on the Si atom sublimation step and the C atom sublimation step.

[0139] In addition, the raw material transportation step includes: an epitaxial growth layer formation step of forming an epitaxial growth layer on the surface of the semiconductor substrate as the raw material transportation destination based on the above step flow growth.

[0140] The heating step can be understood as Si2C or SiC2, etc. diffusing in the raw material transportation space Y becoming supersaturated and condensing at the transportation destination. The growth layer formation in Embodiment 1 can be understood to be based on Physical Vapor Transport.

[0141] The driving force for raw material transportation in Embodiment 1 can be understood, for example, as the temperature difference between the semiconductor substrates 10 caused by the temperature gradient formed within the temperature distribution evaluation unit U.

[0142] It can be understood that the chemical potential difference caused by the crystal structures of the opposite semiconductor substrate surfaces is also the driving force for raw material transportation. For example, it can be understood that in the temperature distribution evaluation unit U including the opposite single crystal substrate surface and polycrystalline substrate surface, the vapor pressure difference caused by the crystal structures of the substrate surfaces can become the driving force for raw material transportation.

[0143] The change amount measurement step S40 measures the substrate thickness change amount A (etching amount E and / or growth amount G) of the semiconductor substrate 10. At this time, the substrate thickness change amount A is measured by obtaining the uneven shape through cross-sectional observation or surface observation. It can also correspond to different points on the surface of the same semiconductor substrate 10 respectively. In particular, in this embodiment, since the substrate thickness change at the portion where the semiconductor substrate 10 abuts against the setting tool 50 is suppressed, the substrate thickness change amount A can be easily measured using a laser microscope or the like.

[0144] The change amount comparison step S50 in Embodiment 1 evaluates the temperature distribution in the heating region 40A based on the substrate thickness change amount A obtained through the change amount measurement step S40.

[0145] The evaluation step in Embodiment 1 evaluates the temperature distribution in the heating region 40A based on, for example, the substrate thickness change amount A, the partial pressure difference corresponding to the surface of the semiconductor substrate 10, the surface density, the desorption coefficient, the molecular weight of the sublimated gas, and the gas constant. This partial pressure difference is determined based on the vapor pressure and temperature difference corresponding to the surface of the semiconductor substrate 10 respectively.

[0146] According to the temperature distribution evaluation device of this embodiment, by using the setting tool 50 to oppose the semiconductor substrate 10 and the transceiver 20, the etching amount E and the growth amount G can be easily measured. That is, in the first contact surface 52 (or the second contact surface 53) that abuts against the semiconductor substrate 10 (or the transceiver 20) and the setting tool 50, etching or growth is suppressed. Therefore, a step corresponding to the growth amount G or the etching amount E is formed at the surface after the heating step S30. By measuring the height of this step, the substrate thickness change amount A can be easily obtained.

[0147] Furthermore, according to the temperature distribution evaluation device of this embodiment, by arranging a plurality of temperature distribution evaluation units U within the heating region 40A, the substrate thickness change amount A of the measurement point P set in the heating region 40A can be obtained with a small area of the semiconductor substrate 10.

[0148] <Embodiment 2>

[0149] Hereinafter, the temperature distribution evaluation device according to Embodiment 2 of the present invention will be described in detail. In addition, in this embodiment, structural elements that are substantially the same as those shown in the aforementioned temperature distribution evaluation method and Embodiment 1 are denoted by the same reference numerals and their description is simplified.

[0150] The temperature distribution evaluation device according to Embodiment 2 includes a semiconductor substrate 10 and a storage container 30 that stores the semiconductor substrate 10. In this storage container 30, at least a part of the container is constituted by a transceiver 20.

[0151] The semiconductor substrate 10 is set to have an area spanning a plurality of measurement points P set in a heating region 40A. For example, wafers of 2 inches (about 5.08 cm) or more, 4 inches (about 10.16 cm) or more, 6 inches (about 15.24 cm) or more, 8 inches (about 20.32 cm) or more can be exemplified.

[0152] The storage container 30 is made of polycrystalline SiC, for example. In this way, the storage container 30 itself can be constituted by the transceiver 20 that transports raw materials to and from the semiconductor substrate 10.

[0153] In addition, in the case of adopting a structure in which the semiconductor substrates 10 are opposed to each other using a setting tool 50 in the same manner as in Embodiment 1, the material of the storage container 30 can be the above-mentioned high melting point material.

[0154] In addition, although not shown, a container can be further arranged outside the storage container 30.

[0155] With the temperature distribution evaluation device according to Embodiment 2, by adopting the semiconductor substrate 10 having an area spanning a plurality of measurement points P, the temperature distribution of the heating region 40A can be evaluated in a larger range. In particular, since the threshold value of the isothermal range in the heating region 40A can be grasped, it is possible to contribute to temperature management in the semiconductor manufacturing process and improve the yield of semiconductor device manufacturing.

[0156] <Reference Example>

[0157] As Figure 8 shown, the substrate thickness change rate R1 has a distance dependence between the transport source and the transport destination.

[0158] In Figure 8In the raw material transportation, the transportation source and the transportation destination are the semiconductor substrate 10 and the storage container 30, respectively. The material of the storage container 30 is polycrystalline SiC. At this time, by inserting a spacer at one end of the semiconductor substrate 10 to give an inclination, the distance dependence between the transportation source and the transportation destination is grasped. It can be understood that when the distance between the transportation source and the transportation destination is in the range of 1.7 to 2.7 mm, the substrate thickness change rate R1 increases.

[0159] 《Example》

[0160] The temperature distribution evaluation (example) was attempted by the following method. In addition, the conditions of the example are described below.

[0161] <Measurement point setting step S10>

[0162] In the measurement point setting step S10, measurement points P1 to P7 were set for the heating region 40A with a diameter of 15 cm. Specifically, the measurement point P1 was set at a position -7.5 cm from the approximate center of the heating region 40A, the measurement point P2 was set at a position -5.0 cm from the approximate center of the heating region 40A, the measurement point P3 was set at a position -2.5 cm from the approximate center of the heating region 40A, the measurement point P4 was set at a position 0.0 cm from the approximate center of the heating region 40A, the measurement point P5 was set at a position 2.5 cm from the approximate center of the heating region 40A, the measurement point P6 was set at a position 5.0 cm from the approximate center of the heating region 40A, and the measurement point P7 was set at a position 7.5 cm from the approximate center of the heating region 40A.

[0163] In addition, the measurement points P1 to P7 are arranged in a straight line.

[0164] <Substrate placement step S20>

[0165] In the substrate placement step S20, the temperature distribution evaluation unit U, which is opposed to the following semiconductor substrate 10 by the setting tool 50, is arranged at positions corresponding to the measurement points P1 to P7. In addition, the temperature distribution evaluation unit U is housed in the storage container 30.

[0166] [Semiconductor substrate 10]

[0167] Substrate material: 4H-SiC single crystal

[0168] Substrate size: 12 mm (width), 4 mm (length), 0.3 mm (thickness)

[0169] Deviation direction and deviation angle: Deviation of 4° in the <11-20> direction

[0170] [Setting tool 50]

[0171] Component material: polycrystalline SiC

[0172] Component dimensions: 0.3 mm (setting tool gap), 0.2 mm (setting tool frame width), 8 mm × 3 mm (setting tool frame length)

[0173] [Storage container 30]

[0174] Container material: TaC

[0175] Tantalum silicide layer:

[0176] Container dimensions: 160 mm (diameter), 60 mm (height)

[0177] [Heating step S30]

[0178] The semiconductor substrate 10 arranged under the conditions of the above substrate arrangement step S20 was heated under the following heating conditions.

[0179] [Heating conditions]

[0180] Heating temperature: 1800 °C

[0181] Temperature gradient: 1 °C / mm

[0182] Heating duration: 1 h

[0183] [Change amount measurement step S40]

[0184] Figure 9 An explanatory diagram showing the measurement of the substrate thickness change amount A at measurement points P1 to P7 and its conversion to the substrate thickness change rate R1 is shown. The substrate thickness change amount A was measured using a laser microscope. In addition, the etching amount E of the semiconductor substrate 10 arranged on the high-temperature side and the growth amount G of the semiconductor substrate 10 arranged on the low-temperature side are approximately the same value.

[0185] [Change amount comparison step S50]

[0186] As Figure 9 shown, the substrate thickness change rate R1 measured in the temperature evaluator 1 after heating depends on the distance from the approximate center of the heating region 40A. In addition, from Figure 9 it can be seen that in the heating region 40A, the range from measurement point P3 to measurement point P5 can be evaluated as a uniform heating region. In addition, even within the range from measurement point P2 to measurement point P6, it can be evaluated as a temperature range that will not have an adverse effect on the semiconductor manufacturing process.

[0187] In addition, it can be understood that the position dependence of the substrate thickness change rate R1 in this embodiment is, for example, a temperature drop at substantially the end of the heating region 40A caused by the generation of heat flow at the contact point between the support column supporting the storage container 30 and the storage container 30.

[0188] According to the present invention, while maintaining the quasi-closed space in the storage container, the temperature distribution in the heating region can be appropriately evaluated. Thus, the temperature distribution evaluation in the region sealed with a material that does not transmit infrared rays or the like can be achieved.

[0189] Furthermore, according to the present invention, raw material transportation is performed in a space where the distance between semiconductor substrates is the same, with the partial pressure difference between the substrate surfaces as the driving force. Thus, the in-plane deviation of the etching rate and the growth rate of the epitaxial growth layer can be suppressed, and the temperature distribution evaluation based on the substrate thickness change amount can be appropriately performed.

[0190] Description of Reference Numerals

[0191] 10 Semiconductor substrate

[0192] 20 Transceiver

[0193] 30 Storage container

[0194] 40 Heating device

[0195] 40A Heating region

[0196] 50 Setting tool

[0197] D1 Horizontal direction

[0198] D2 Vertical direction

Claims

1. A method for evaluating a temperature distribution, which evaluates the temperature distribution in a heating region of a heating device, wherein, In the heating region, a semiconductor substrate and a transceiver for mutually transporting raw materials with the semiconductor substrate are heated, and the temperature distribution in the heating region is evaluated based on the change amount of the substrate thickness of the semiconductor substrate, where the raw materials are sublimation gases generated from at least one of the semiconductor substrate and the transceiver.

2. The temperature distribution evaluation method according to claim 1, wherein The semiconductor substrate and the transceiver are disposed opposite to each other and heated so as to form a temperature gradient between the semiconductor substrate and the transceiver.

3. The temperature distribution evaluation method according to claim 1, wherein, The change amount of the substrate thickness is a quantity that changes with the temperature gradient formed in the heating region as the driving force.

4. The temperature distribution evaluation method according to any one of claims 1 to 3, comprising: a measurement point setting step of setting a plurality of measurement points in the heating region; a substrate disposition step of disposing the semiconductor substrate and the transceiver at positions corresponding to the measurement points; a change amount measurement step of measuring the change amount of the substrate thickness of the semiconductor substrate corresponding to the measurement points; and a change amount comparison step of comparing a plurality of the change amounts of the substrate thickness.

5. The temperature distribution evaluation method according to claim 4, wherein, The measurement point setting step sets a plurality of the measurement points in the horizontal direction of the heating region.

6. The temperature distribution evaluation method according to claim 4, wherein, The measurement point setting step sets a plurality of the measurement points in the height direction of the heating region.

7. The temperature distribution evaluation method according to claim 4, wherein The substrate disposition step disposes a plurality of the semiconductor substrates along the measurement points.

8. The temperature distribution evaluation method according to any one of claims 1 to 3, wherein, The change amount of the substrate thickness is an etching amount or a growth amount.

9. The temperature distribution evaluation method according to any one of claims 1 to 3, wherein, The semiconductor substrate and the transceiver are selected from any materials of SiC, GaN, and AlN.

10. A temperature distribution evaluation device, comprising: a temperature distribution evaluation unit disposed in the heating region of a heating device, wherein the temperature distribution evaluation unit has: a semiconductor substrate; and a transceiver that mutually transports raw materials by being opposed to and heated with the semiconductor substrate, where the raw materials are sublimation gases; the temperature distribution evaluation device is used to evaluate the temperature distribution in the heating region based on the change amount of the substrate thickness of the semiconductor substrate.

11. The temperature distribution evaluation device according to claim 10, wherein, The temperature distribution evaluation unit has: a setting tool for relatively setting the semiconductor substrate and the transceiver.

12. The temperature distribution evaluation device according to claim 11, wherein, The setting tool is provided with: a first abutting surface that abuts against the semiconductor substrate; and a second abutting surface that abuts against the transceiver.

13. The temperature distribution evaluation device according to claim 11, wherein, The setting tool has: a positioning unit for positioning the semiconductor substrate and / or the transceiver.

14. The temperature distribution evaluation device according to claim 13, wherein, The positioning unit is a frame portion provided along the edge of the semiconductor substrate and / or the transceiver.

15. The temperature distribution evaluation device according to any one of claims 10 to 14, wherein, A plurality of the temperature distribution evaluation units are included.

16. The temperature distribution evaluation device according to any one of claims 10 to 14 further comprises: a storage container for storing the temperature distribution evaluation unit, where the storage container forms an atmosphere containing elements constituting the semiconductor substrate inside the container during heating.

17. The temperature distribution evaluation device according to any one of claims 10 to 14 further comprises: a storage container for storing the semiconductor substrate, where a part of the storage container is constituted by the transceiver.

18. The temperature distribution evaluation device according to any one of claims 10 to 14, wherein, The semiconductor substrate and the transceiver are selected from any materials of SiC, GaN, and AlN.

19. A method for evaluating a soaking range, wherein, In the heating region of the heating device, the semiconductor substrate and the transceiver for mutually transporting raw materials with the semiconductor substrate are heated at a plurality of measurement points in the heating region, and the isothermal range of the heating region is evaluated based on the change amount of the substrate thickness of the semiconductor substrate, where the raw material is a sublimation gas generated from at least one of the semiconductor substrate and the transceiver.

20. The evaluation method of the soaking range according to claim 19, wherein, The semiconductor substrate and the transceiver are disposed opposite to each other, and heating is performed such that a temperature gradient is formed between the semiconductor substrate and the transceiver.

21. The method for evaluating the isothermal range according to claim 19 or 20, comprising: a measurement point setting step of setting a plurality of measurement points in the heating region; a substrate disposition step of disposing the semiconductor substrate and the transceiver at positions corresponding to the measurement points; a heating step of changing the substrate thickness of the semiconductor substrate by heating the semiconductor substrate and the transceiver in the heating region; a change amount measurement step of measuring the change amount of the substrate thickness of the semiconductor substrate corresponding to the measurement points; and a change amount comparison step of comparing the change amounts of the substrate thicknesses at the plurality of measurement points.

22. The evaluation method of the soaking range according to claim 19 or 20, wherein, The heating temperature of the semiconductor substrate and the transceiver is 1600 °C or higher.

23. The evaluation method of the soaking range according to claim 19 or 20, wherein, The heating temperature of the semiconductor substrate and the transceiver is 1800 °C or higher.

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