Wafer processing apparatus

Abstract

In order to provide a wafer processing apparatus having improved processing accuracy and yield, the wafer processing apparatus comprises: a processing chamber (5) disposed inside a vacuum container (1); a sample stage (4) which is disposed in the center of the lower part in the processing chamber and on which a wafer (W) to be processed is placed and supported; a gas introduction part (6) which is disposed above the central part of the upper surface of the sample stage and has a gas introduction port (11) for introducing a gas for processing the wafer into the processing chamber; and a lamp unit (2) disposed around the gas introduction part and constituting the top surface of the processing chamber, the lamp unit comprising: a plurality of annular lamps (2a) disposed around the gas introduction part in a multiple manner and irradiating the wafer on the sample stage with electromagnetic waves; and a reflection member (2) that is disposed annularly around the gas introduction unit above the plurality of lamps and has a reflection surface configured so as to be capable of reflecting electromagnetic waves emitted from the plurality of lamps downward and toward a region on the center side of the processing chamber, the reflection surface having a higher height at a location close to the gas introduction unit, and the reflection surface having a lower height than the reflection surface at a location close to the gas introduction unit, the reflection surface being configured so as to be capable of reflecting electromagnetic waves emitted from the plurality of lamps toward the region on the center side of the processing chamber. The gas inlet portion becomes lower toward the outer peripheral side from the gas inlet portion.

Description

Technical Field

[0001] The present invention relates to a wafer processing apparatus. Background Art

[0002] In semiconductor devices, due to the requirements of low power consumption and increased storage capacity, further miniaturization and three-dimensionalization of device structures have been continuously developed. In the manufacture of three-dimensional structured devices, since the structure is three-dimensional and complex, in addition to the conventional "vertical etching" that etches in the direction perpendicular to the wafer surface, "isotropic etching" that can also etch in the lateral direction is required.

[0003] As an example of the prior art for performing isotropic etching with high precision by dry processing, an adsorption / desorption type etching method described in Japanese Patent Application Laid-Open No. 2015-185594 (Patent Document 1) is known. In this prior art, radicals initially generated by plasma are adsorbed onto the surface of the etched layer of the object to be processed placed on a worktable disposed inside the processing chamber, and a reaction layer is formed by a chemical reaction (adsorption step). Then, heat energy is applied to cause the reaction layer to desorb and be removed (desorption step). Etching is performed by alternately repeating this adsorption step and desorption step in a cycle.

[0004] In this prior art, in order to apply heat energy to the surface of the object to be processed in the desorption step, a lamp that emits electromagnetic waves in the ultraviolet or infrared region is provided above the worktable disposed in the processing chamber. In the desorption step, the object to be processed is heated to the temperature at which the reaction layer on the surface of the etched layer sublimes in a short time.

[0005] In addition, in Japanese Patent Application Laid-Open No. 2020-097060 (Patent Document 2), a worktable is provided inside a processing chamber disposed inside a vacuum container, and is provided with: an annular IR lamp, which is multiply disposed around a flow path for supplying reactive particles such as radicals directly above the worktable, and irradiates electromagnetic waves in the infrared region (hereinafter, referred to as infrared light or IR or IR light); and a reflector, which is disposed above these IR lamps and reflects the IR light radiated from the IR lamps toward the upper surface of the wafer worktable in the processing chamber below or the wafer placed on the upper surface. With this structure in this prior art, the wafer is irradiated with the IR light reflected by the reflector together with the IR light directly irradiated from the IR lamp, and the wafer is heated in a short time.

[0006] Prior Art Documents

[0007] Patent Documents

[0008] Patent Document 1: Japanese Patent Application Laid-Open No. 2015-185594

[0009] Patent Document 2: Japanese Patent Application Laid-Open No. 2020-097060 Summary of the Invention

[0010] Problems to be Solved by the Invention

[0011] As in the above-mentioned prior art, particles (etchants) of a reactive gas or vapor supplied into the processing chamber in the container are supplied downward from the inlet, which is disposed above the center of the upper surface of the sample stage. The sample stage is disposed at the center of the interior of the processing chamber and a wafer is placed and supported above it. The etchant adheres in contact with the upper surface of the wafer and reacts with the surface of the film of the processing object having a film structure of a plurality of film layers including the film layer to be processed, which is previously disposed on the upper surface of the wafer. The amount and the distribution of the size of the reaction on the upper surface of the wafer are greatly affected, for example, by the balance between the amount of the supplied etchant and the reaction temperature.

[0012] The amount of the supplied etchant varies greatly depending on the flow path of the reactive gas or vapor. Therefore, in order to suppress the deviation of the amount of the etchant in the radial or circumferential direction (in-plane direction) on the upper surface of the wafer, a structure in which the etchant particles reaching the wafer are exhausted from the space between the sample stage and the inner wall of the surrounding processing chamber after moving from the center of the wafer toward the outer periphery is desired. Specifically, a structure in which exhaust is performed in a coaxial arrangement where the central axis in the vertical direction of the annular space located on the outer peripheral side of the sample stage and surrounding the outer peripheral wall of the sample stage coincides with or is disposed at a position approximate thereto with respect to the opening of the gas inlet, the center of the wafer, and the coaxial arrangement (coaxial exhaust) is desired. The above-mentioned prior art has this coaxial exhaust structure.

[0013] On the other hand, in these prior arts, in a structure in which a wafer is heated using an IR (infrared) lamp, in order to ensure the heating speed and the accuracy of the obtained temperature distribution, it is required to irradiate IR light with a desired intensity and amount over the entire range of the upper surface of the wafer. However, in the above-mentioned prior art, when the gas inlet is disposed above the center of the wafer, the IR lamp is not disposed directly above the center of the wafer and has to be located around the gas inlet. Therefore, in such a structure, while adjusting the temperature of the central portion of the wafer or the temperature of the wafer and the distribution in the in-plane direction of the wafer to a desired value, the accuracy may be impaired. This may cause a deviation in the shape and a relative reduction in the accuracy of the etched region in the central portion compared to the outer peripheral side portion of the upper surface of the wafer.

[0014] An object of the present invention is to provide a wafer processing apparatus with improved processing accuracy and yield.

[0015] Means for Solving the Problems

[0016] The above problem is solved by a wafer processing apparatus, which includes: a processing chamber disposed inside a vacuum container; a sample stage disposed at the center of the lower part inside the processing chamber, on which a wafer to be processed is placed and supported; a gas introduction unit disposed above the center of the upper surface of the sample stage and having a gas inlet for introducing a gas for processing the wafer into the processing chamber; and a lamp unit disposed around the gas introduction unit and constituting the top surface of the processing chamber. The lamp unit includes: a plurality of annular lamps arranged multiple times around the gas introduction unit, which irradiate electromagnetic waves onto the wafer on the sample stage; and a reflection member annularly disposed around the gas introduction unit above the plurality of lamps and having a reflection surface configured to reflect the electromagnetic waves emitted from the plurality of lamps downward and toward the central side region of the processing chamber. The height of the reflection surface is higher at a position closer to the gas introduction unit and becomes lower as it moves from the gas introduction unit toward the outer peripheral side.

[0017] Advantages of the Invention

[0018] According to the present invention, the electromagnetic waves emitted from the lamp can be reflected in a specified direction upward, so that the temperature value and its distribution of the wafer can be changed to desired values. Thereby, the temperature accuracy of the wafer being processed can be well within a range suitable for processing, and the yield of the processing can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a longitudinal sectional view schematically showing the outline of the structure of a wafer processing apparatus according to an embodiment of the present invention.

[0020] Figure 2 is schematically showing Figure 1 a longitudinal sectional view schematically showing the outline of the structure of a wafer processing apparatus according to a modified example of the embodiment shown.

[0021] Figure 3 is schematically showing in Figure 2 the modified example shown, a longitudinal sectional view schematically showing the outline of the structure in the case where the reflection surfaces of a plurality of movable reflection plates are parallel to the upper surface of the wafer, and a graph showing the temperature distribution in the radial direction of the upper surface of the wafer in this case.

[0022] Figure 4 is schematically showing in Figure 2 the modified example shown, a longitudinal sectional view schematically showing the outline of the structure in the case where the reflection surfaces of a plurality of movable reflection plates are inclined with respect to the upper surface of the wafer and reflect IR light toward the center of the wafer, and a graph showing the temperature distribution in the radial direction of the upper surface of the wafer in this case.

[0023] Figure 5 is showing in Figure 2In the illustrated modification example, a graph showing an example of the magnitudes of the intensities (illuminances) of the IR direct light and the IR reflected light at the positions on the two IR lamps, the reflector, and the wafer W thereunder, which vary with the tilt angle of the reflecting surface of the reflector.

[0024] Figure 6 is a diagram schematically showing Figure 5 a model of the configuration of an IR lamp unit for calculating an example of the change in the intensity of the IR light shown.

[0025] Figure 7 is a graph showing an example of the distribution of the intensity (illuminance) of the IR light in the radial direction on the upper surface of the wafer when the angle of the reflector shown Figure 2 is tilted by a specified value. DETAILED DESCRIPTION

[0026] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Hereinafter, examples and modification examples of the present invention will be described. Figures 1 to 7 using

[0027] Figure 1 is a longitudinal sectional view schematically showing an outline of the structure of a wafer processing apparatus according to an embodiment of the present invention. The wafer processing apparatus 100 of the present embodiment generally includes: a processing container capable of being depressurized inside; a gas supply unit connected to the upper part of the processing container for supplying a processing gas for processing a specimen on a substrate such as a semiconductor wafer to be processed into the processing container; and an exhaust unit connected to the lower part of the processing container for discharging the gas inside the processing container. In the wafer processing apparatus 100, the processing container is connected to a vacuum container (not shown) that transports the specimen to be processed in the internal space, and an opening (door) (not shown) serving as a passage through which the specimen passes inside is provided on the side wall of the processing container between the inside of the transport container and the inside of the processing container.

[0028] The processing container includes: a vacuum container 1, which is a metal container and has a processing chamber 5 with a cylindrical space inside; and a specimen stage 4 disposed below the inside of the processing chamber 5 for mounting, holding, or supporting a wafer W, which is a specimen to be processed, on its upper surface. In addition, a gas introduction unit 6 is disposed above the central part of the processing chamber 5, and the processing gas, dilution gas, or cleaning gas supplied to the processing chamber 5 flows in the internal space in a tubular or cylindrical shape. The gas introduction unit 6 may also be disposed above the central part of the top surface of the processing chamber 5, and the lower end portion is exposed into the internal space of the processing chamber 5 to form the top surface of the processing chamber 5.

[0029] At the lower end of the gas introduction unit 6, a dielectric gas introduction plate 10 having a disc shape is disposed. At least one gas introduction port 11 is disposed at the central portion of the gas introduction plate 10. The gas introduction port 11 allows a gas such as a processing gas that has passed through the cylindrical space inside the gas introduction unit 6 to pass through the inside and be introduced into the processing chamber 5. In this example, the particles of the processing gas that enter the processing chamber 5 through the gas introduction port 11 diffuse inside the processing chamber 5 and adhere to a multi-layer film structure including a film layer to be processed and a mask film layer that is previously disposed on the upper surface of the wafer W placed on the upper surface of the sample stage 4. The adhered gas particles interact or react with the material on the surface of the film layer to be processed, forming a desired product.

[0030] Furthermore, a lamp unit 2 is provided. The lamp unit 2 forms the upper part of the vacuum chamber 1 and is disposed to surround the outer periphery of the gas introduction unit 6 above the processing chamber 5. The lamp unit 2 of this example has an IR lamp 2a that can irradiate infrared light (IR light) into the processing chamber 5 to heat the wafer W placed on the upper surface of the sample stage 4, and is disposed in a concentric shape surrounding the outer periphery of the gas introduction unit 6 in multiple layers (triple in this figure). Moreover, the lamp unit 2 is a flat annular member made of a member through which IR light can pass, and has a transmissive window 2b that forms the top surface of the processing chamber 5 around the lower end of the gas introduction unit 6.

[0031] Moreover, the lamp unit 2 of this example has a dome cover 3 above the IR lamp 2a. The dome cover 3 is a plate-shaped member that surrounds the outer periphery of the gas introduction unit 6 and covers the IR lamp 2a and the transmissive window 2b, and has a curved shape with a higher central portion and a lower peripheral portion. The dome cover 3 has a circular opening at the central portion and has an annular shape when viewed from above, and the inner peripheral edge portion is disposed to surround the outer periphery of the gas introduction unit 6. And the outer surface and the lower surface (inner surface) of the dome cover 3 are inclined so as to become lower from the central portion toward the peripheral edge portion, and the inclination angle has a so-called dome shape that becomes larger as it goes from the center to the periphery.

[0032] The inner surface of the cover dome 3 has such a shape that it is configured to function as a reflecting surface for reflecting the IR light emitted from the IR lamp 2a. As a result, at least a part of the IR light irradiated from the annularly arranged IR lamps 2a is reflected by the inner surface of the cover dome 3 toward the center and downward of the processing chamber 5. That is, in the example of this figure, the cover dome 3 serves as an IR light reflecting member, and the lower surface (inner surface) serves as a reflecting surface. The IR light (IR reflected light) emitted from each IR lamp 2a and reflected by the inner side wall surface of the cover dome 3 travels downward and toward the center of the upper surface of the worktable 4. Through the gaps between the multiple annularly arranged IR lamps 2a and the gap with the gas introduction unit 6, when a wafer W is placed above the upper surface of the specimen stage 4, it irradiates the central side surface of the wafer W.

[0033] That is, the IR light emitted upward from each IR lamp 2a is reflected by the inner surface of the cover dome 3 and irradiates the wafer W through the space closer to the center side of the wafer W than each IR lamp 2a. As a result, in the region on the center side of the upper surface of the wafer W, in addition to the IR light (IR direct light) that directly reaches the IR lamp from the IR lamp 2a, more IR reflected light is irradiated compared to the outer peripheral side region, and IR light of a greater intensity or amount is irradiated.

[0034] The lower part of the vacuum container 1 is connected to an exhaust section including an exhaust pump 16 and an exhaust pipe 13 connected thereto. In the exhaust section, one end of the exhaust pipe 13 is connected to the bottom surface of the vacuum container 1, and the inside of the exhaust pipe 13 communicates with the inside of the processing chamber 5 via an exhaust port 12 disposed below the specimen stage 4 and facing the lower part of the processing chamber 5. In the exhaust section, between the other end of the exhaust pipe 13 connected to the exhaust port 12 and the inlet of the exhaust pump 16, a flow rate regulating valve 15 for regulating the flow rate or speed of the waste gas from the processing chamber 5 flowing inside the exhaust pipe 13 is provided, and the flow rate regulating valve 15 is connected to the exhaust pump 16 through an exhaust pipe 14.

[0035] The upper end of the gas introduction unit 6 is connected to a gas supply section. The gas supply section includes: a plurality of gas storage sections 9 such as tanks that separately store each gas inside; a gas supply pipeline 7 whose one end is connected to each gas storage section and the other end is connected to the upper end of the gas introduction unit 6, including a pipe for the gas from the gas storage section to flow inside; and a gas flow regulator 8 such as an MFC (mass flow controller) disposed on the gas supply pipeline 7 between the gas storage section 9 and the gas introduction unit 6 to regulate the flow rate or speed of the flowing gas. The pressure inside the processing chamber 5 is adjusted to a value within a range suitable for processing by the balance between the flow rate per unit time of the gas introduced into the processing chamber 5 from the gas introduction port 11 and the flow rate per unit time of the particles such as gas discharged from the processing chamber 5 through the exhaust port 12.

[0036] UseFigure 2 A modification of an embodiment of the present invention will be described. Figure 2 schematically shows Figure 1 a longitudinal sectional view showing a schematic structure of a wafer processing apparatus according to a modification of the illustrated embodiment. Figure 1 The difference between the illustrated embodiment and the modification shown in this figure is that the lamp unit 2 of the wafer processing apparatus 200 of the modification includes: a plurality of reflector units 21, 22, 23, which are each formed in a shape of a plurality of flat plates having reflectors arranged in a multiple concentric ring shape above each of the IR lamps 2a arranged in a multiple concentric ring shape; and a dome 3', which is arranged on the outer peripheral side of the gas introduction unit 6 and covers the reflector units 21 to 23, the IR lamps 2a, and the transmission window 2b above the reflector units 21 to 23, and has a curved upper and lower surface that is high at the central portion and low at the outer peripheral portion.

[0037] In the reflector units 21, 22, 23 of this example, when viewed from above the axis (central axis) in the vertical direction passing through the center of the wafer W or the circular sample stage 4, a plurality of reflectors 21a, 21b,..., 22a, 22b,..., 23a, 23b,... each formed of a plurality of square flat members and having a surface (reflective surface) capable of reflecting IR light are arranged in a ring shape at three radial positions having different lengths in the radial direction from the center and at three circumferences having different heights from the upper surface of the wafer W. The surfaces (upper surfaces) on the sides opposite to the respective reflective surfaces of the plurality of reflectors 21a, 21b,..., 22a, 22b,..., 23a, 23b,... are connected to an angle adjustment mechanism on the lower side (inner side) of the lower surface of the dome 3', whereby the reflective surface of the IR light from the IR lamp 2a can be inclined so as to face the processing chamber 5 or the sample stage 4 or the center of the wafer W.

[0038] In this example, the reflector units 21, 22, 23 are each configured as a plurality of sets of reflectors 21a, 21b,..., 22a, 22b,..., 23a, 23b,... The central portions of the reflective surfaces of the reflectors are arranged for each reflector unit at positions where the radius from the central axis of the wafer W or the worktable 4 or the processing chamber 5 is made to coincide with or approximate to the radius of each of the three IR lamps 2a arranged in a ring shape. And the height from the upper surface of the wafer W at the positions where the central portions of the reflective surfaces of the reflectors belonging to these three reflector units 21 to 23 are arranged increases in each set of each reflector as it approaches the center of the processing chamber 5 or the sample stage 4 or the wafer W. That is, the positions of the centers of the reflectors 21a, 21b,... are arranged at the highest positions from the wafer W, and the distance in the vertical direction from the IR lamp 2a is also the largest.

[0039] In such a structure, when the reflecting surfaces of the reflecting plates 21a, 21b, …, 22a, 22b, …, 23a, 23b, … of the respective reflecting plate units 21, 22, 23 are held at a prescribed angle such that the IR light (IR reflected light) to be reflected faces the center of the processing chamber 5 or the upper surface of the stage 4 and the wafer W, the reflected IR light (IR reflected light) travels downward and toward the center of the upper surface of the wafer W, and irradiates the upper surface of the wafer W through the gaps between the IR lamps 2a arranged in a multiple-ring shape and the gap with the gas introduction unit 6. That is, the IR light radiated upward from each IR lamp 2a is reflected by the respective reflecting plate units 21, 22, 23 and irradiates the wafer W through the space closer to the center side of the wafer W than the respective IR lamps 2a. As a result, in the region on the center side of the upper surface of the wafer W, in addition to the IR light (IR direct light) that directly reaches the IR lamp from the IR lamp 2a, more IR reflected light is irradiated and IR light of a greater intensity is irradiated compared to the outer peripheral side region.

[0040] On the other hand, when the above-described reflecting surface is held parallel to the upper surface of the wafer W, similarly to the above case, although the IR direct light and the IR reflected light are irradiated onto the upper surface of the wafer W, the intensity of the IR reflected light irradiated onto the region on the central side of the wafer W is relatively reduced compared to the case where the reflecting plates of the respective reflecting plate units 21, 22, 23 are inclined such that the IR reflected light faces the center side. And in this example, the lower end portion of the gas introduction unit 6 constitutes the central portion of the top surface of the processing chamber 5, and the IR lamp is arranged above the central portion, and it is not possible to irradiate with a strong intensity obtained when the IR direct light of the IR lamp 2a is incident on the upper surface of the wafer W vertically or at an angle close to vertical. Therefore, regarding the intensity and amount of the IR direct light, the intensity and amount of the IR direct light also become relatively smaller compared to the light irradiated toward the outer peripheral side.

[0041] Figure 3 is a diagram schematically showing an example of the temperature distribution on the wafer obtained when the reflecting surface of the reflecting plate of the modified example shown Figure 2 is held parallel to the specimen stage or the wafer. It should be noted that in this figure, the IR direct light is indicated by a solid-line arrow and the IR reflected light is indicated by a dashed-line arrow. As described above, in the example shown in this figure, the IR direct light radiated downward from the lamp unit 2 directly irradiates the upper surface of the wafer W arranged below from the IR lamp 2a. On the other hand, the IR light radiated upward from the IR lamp 2a becomes IR reflected light reflected downward by the reflecting surface of the reflecting plate of any one of the reflecting plate units 21 to 23, and irradiates the upper surface of the wafer W below the gap through the gap between the IR lamps 2a having a ring shape arranged in a triple concentric shape.

[0042] As described above, in the example shown in the figure, the intensity or amount of the IR direct light and the IR reflected light emitted from the lamp unit 2 becomes greater in the peripheral region than in the region on the central portion side of the wafer W. Therefore, the temperature of the upper surface of the wafer W has a distribution in which the region on the central portion side is relatively low and the region on the peripheral side is relatively high.

[0043] Figure 4 is a diagram schematically showing Figure 2 an example of the temperature distribution on the wafer obtained when the reflecting surface of the reflector of the modified example shown is held facing the center of the specimen stage or the wafer. It should be noted that in this figure, the IR direct light is also indicated by a solid-line arrow, and the IR reflected light is indicated by a dashed-line arrow. As described above, in the example shown in this figure, the IR direct light radiated downward from the lamp unit 2 directly irradiates the upper surface of the wafer W disposed below from the IR lamp 2a. On the other hand, the IR light radiated upward from the IR lamp 2a becomes IR reflected light reflected by the reflecting surface of the reflector of any of the reflector units 21 to 23 so as to face downward and toward the center of the wafer W, and irradiates the upper surface of the wafer W below the gap between the annular IR lamps 2a arranged in a triple concentric shape through the gap therebetween.

[0044] In addition, the IR light radiated upward from the IR lamp 2a-1 disposed on the innermost periphery is IR reflected light reflected downward and toward the central region side of the wafer W by the reflectors 21a, 21b,... and travels further toward the center of the wafer W through the gap between the innermost peripheral IR lamp 2a-1 and the outer peripheral edge of the lower end portion of the gas introduction unit 6, and irradiates the upper surface of the wafer W. As described above, in addition to the structure made of a material through which IR light can pass, the lower end portion of the cylindrical side wall of the gas introduction unit 6 or the gas introduction plate 10 may also be made of a material that transmits IR light. In this case, through the gas introduction unit 6 provided at the central portion of the top surface of the processing chamber 5, the IR reflected light reflected by at least any one of the reflector units 21 to 23 irradiates the central portion of the wafer W where the intensity or amount of the IR direct light is small with a greater intensity or amount. Therefore, the intensity or amount of the IR reflected light becomes greater in the central region than in the peripheral region of the wafer W, and the temperature of the upper surface of the wafer W has a distribution in which the region on the central portion side is relatively high and the region on the peripheral side is relatively low.

[0045] Use Figure 5 、 6 to Figure 2 illustrate an example of the degree of inclination of the reflecting surface of the reflector of the lamp unit 2 and the change in the intensity (illuminance) of the IR direct light and the IR reflected light from the IR lamp 2a in the modified example shown. Figure 5 is a diagram showing Figure 2In the illustrated modification example, a graph showing an example of how the intensities (illuminances) of the IR direct light and the IR reflected light at the positions on the two IR lamps, the reflector, and the wafer W below it change as the tilt angle of the reflecting surface of the reflector changes. Figure 6 shows the case where Figure 2 the angle of the reflector shown is parallel to the wafer and an example of a graph showing the distribution of the intensity (illuminance) of the IR light in the radial direction on the upper surface of the wafer when the angle of the reflecting surface of the reflector is tilted by a specified value.

[0046] In Figure 5 , Figure 7 , a case where conditions including the arrangement and relative positional relationship between the lamp unit 2 and the wafer W are appropriately set is used as a model, and the change in the intensity of the above-mentioned IR light is calculated under this condition. Figure 6 is a diagram schematically showing a model of the arrangement of an IR lamp unit for calculating Figure 5 an example of the change in the intensity of the IR light shown.

[0047] In Figure 6 , at a position at a height (distance) d1 above the wafer W in the upward direction (vertical direction in the figure) from the upper surface of the wafer W, two IR lamps 2a-1, 2a-2 are arranged separated by a distance L in the horizontal direction (left-right direction in the figure). In addition, reflectors 21a, 22a are arranged at a distance (height) d2 above each of these IR lamps 2a-1, 2a-2. In this figure, the IR lamp 2a-1 on the left side in the figure is Figure 2 the innermost IR lamp in the radial direction from the center of the processing chamber 5 among the IR lamps 2a arranged in a triple ring shape in

[0048] , and the IR lamp 2a-2 on the right side in the figure is the IR lamp at the second position in this radial direction. The reflectors 21a, 22a located above them belong to the reflector units 21, 22 respectively.

[0049] In Figure 5In the figure, reference numeral 502 represents the change in the total intensity of the IR direct light from IR lamps 2a-1 and 2a-2, reference numeral 503 represents the change in the total intensity of the IR reflected light from the reflector plates 21a and 22a, and reference numeral 501 represents the change in the sum of the intensity 502 of the total IR direct light and the intensity 503 of the total IR reflected light. In the example of this figure, it is calculated by setting the distance L as a unit of any size to 5, the height d1 to 5, and the height d2 to 0.1. It is shown that as the inclination angle of the reflector plate 22a increases, the position X moves away from the position B, and the intensity 501 of the IR light at the position X decreases after slightly increasing at the beginning. In particular, in the example of this figure, it is shown that the intensity 501 of the IR light becomes the maximum under the condition that the inclination angle of the reflector plate 22a is small when the position X is between the position A and the position B of Figure 6 The intensity 501 of the IR light becomes the maximum under the condition that the inclination angle of the reflector plate 22a is small when the position X is between the position A and the position B of the reflector plate 22a.

[0050] In Figure 7 it is shown the change in the intensity of the IR light with respect to the change in the distance from the center of the wafer W in the case where the IR lamp 2a and the reflector plate above it are arranged above a specific position in the radial direction from the center of the wafer W and the angle of the reflecting surface is set to a specified value. In this figure, the IR lamp 2a is arranged at the position of the distance at the right end on the graph, reference numeral 602 represents the change in the intensity of the IR direct light from the IR lamp 2a, reference numeral 603 represents the change in the intensity of the IR reflected light from the reflector plate above the IR lamp 2a, and reference numeral 601 represents the change in the sum of the intensity 602 of the IR direct light and the intensity 603 of the IR reflected light. In this figure, it can be seen that as the position in the radial direction from the center on the wafer W approaches the projection part above the IR lamp 2a, the intensity 602 of the IR direct light and the intensity 603 of the IR reflected light become larger.

[0051] Based on the results of the research as described above, the inventors obtained the following insights: In the embodiments and modified examples shown in Figure 1 and 2 , by using a plurality of reflector units 21 to 23 arranged in a ring along circumferences of different radii above the dome-shaped reflector cover dome 3 and the IR lamp 2a respectively, it is possible to form a temperature distribution in which the temperature of the central part of the wafer W is higher than that of the peripheral region. And it is conceived that setting the state parallel to the wafer W as 0°, variably adjusting the angle of the reflecting surface of the above-mentioned reflector units 21 to 23 within the positive and negative ranges, so that the value and distribution of the temperature of the wafer W include so-called medium-high and outer-high and become the desired values.

[0052] On the basis of changing the temperature distribution of the wafer W in this way, the angle adjustment mechanism on which each reflector is installed in the reflector units 21 to 23 has the function of changing the angle of the reflective surface from the area toward the center or the central part of the wafer W or the worktable 4 or the processing chamber 5 to the area toward the peripheral side thereof, for example, the inner peripheral side wall of the processing chamber 5, and can be adjusted to different angles independently in the reflector units 21 to 23. Figure 1 , 2 The control unit (not shown) that receives command signals for adjusting the actions of various parts of the chip processing devices 100 and 200 receives outputs from multiple temperature sensors arranged inside the workbench 4 for detection, and sends signals to the angle adjustment mechanism to make adjustments based on the value or distribution of the temperature of the chip W and the target value or distribution.

[0053] As described in the above-mentioned embodiment and modification, in the present embodiment and modification, by supplying IR reflected light of greater intensity or amount from the lamp unit 2 to the center side of the wafer, or irradiating the desired area of ​​the wafer W with IR reflected light reflected by each of the reflective plates of the reflective plate units 21, 22, and 23 whose angles are appropriately adjusted, it is possible to obtain a value of the temperature during processing of the wafer W suitable for processing and its distribution. As a result, the processing accuracy and yield of the wafer W processed by the wafer processing apparatuses 100 and 200 are improved.

[0054] Description of reference numerals:

[0055] 1…vacuum container, 2…lamp unit, 2a…IR lamp, 2b…transmission window, 3…cover dome, 4…sample table, 5…processing chamber, 6…gas introduction unit, 7…gas supply pipeline, 8…gas flow regulator, 9…gas storage unit, 10…gas introduction plate, 11…gas introduction port, 12…exhaust port, 13, 14…exhaust pipe, 15…flow regulating valve, 16…exhaust pump, 21, 22, 23…reflection plate unit, 21a, 21b, 22a, 22b, 23a, 23b…reflection plate, 100, 200…wafer processing device.

Claims

1. A wafer processing apparatus, wherein, the wafer processing apparatus includes: a processing chamber disposed inside a vacuum container; a sample stage disposed at the center of the lower part inside the processing chamber, on which a wafer to be processed is placed and supported; a gas introduction part disposed above the center of the upper surface of the sample stage and having a gas inlet for introducing a gas for processing the wafer into the processing chamber; and a lamp unit disposed around the gas introduction part and forming the top surface of the processing chamber, the lamp unit includes: a plurality of annular lamps disposed around the gas introduction part in multiple layers, irradiating electromagnetic waves onto the wafer on the sample stage; and a reflection member disposed around the gas introduction part in a ring shape above the plurality of lamps, having a reflection surface configured to reflect the electromagnetic waves radiated from the plurality of lamps downward and toward the central region of the processing chamber, the height of the reflection surface being higher at a position closer to the gas introduction part and becoming lower as it goes from the gas introduction part toward the outer peripheral side.

2. The wafer processing apparatus according to claim 1, wherein, the reflection surface of the reflection member is formed by a curved surface whose height decreases from the end on the center side to the end on the outer peripheral side.

3. The wafer processing apparatus according to claim 1, wherein, the lamp unit includes a plurality of flat reflection plates on the lower side of the reflection member, the plurality of reflection plates being disposed in a ring shape around the gas introduction part and around the center of the sample stage when viewed from above, and the electromagnetic waves reflected by the plurality of reflection plates are irradiated onto the wafer on the sample stage through the gaps between the plurality of lamps or the gaps between the lamps and the gas introduction part.

4. The wafer processing apparatus according to claim 3, wherein, the lamp unit includes a plurality of reflection plate units, the plurality of reflection plate units being formed by the plurality of reflection plates at a plurality of different radius positions around the center of the sample stage when viewed from above and around the gas introduction part.

5. The wafer processing apparatus according to claim 4, wherein, the plurality of reflection plate units each include the plurality of reflection plates constituting each reflection plate unit at different heights from the upper surface of the sample stage.

6. The wafer processing apparatus according to claim 3, wherein, the wafer processing apparatus includes an angle variable mechanism that variably adjusts the angle at which the reflection surface of each of the plurality of reflection plates is inclined with respect to the horizontal plane, so as to adjust the inclination angles of the plurality of reflection plates in such a way that the electromagnetic waves are reflected toward the central side or the outer peripheral side of the sample stage.

7. The wafer processing apparatus according to claim 4, wherein, the wafer processing apparatus includes an angle variable mechanism that variably adjusts the angle at which the reflection surface of each of the plurality of reflection plates is inclined with respect to the horizontal plane, so as to adjust the inclination angles of the plurality of reflection plates in such a way that the electromagnetic waves are reflected toward the central side or the outer peripheral side of the sample stage.

8. The wafer processing apparatus according to claim 5, wherein, The wafer processing apparatus includes an angle variable mechanism that variably adjusts the angle at which the reflecting surface of each of the plurality of reflecting plates is inclined with respect to the horizontal plane, so as to adjust the angles of the plurality of reflecting plates in such a manner that the electromagnetic wave is reflected toward the center side or the outer peripheral side of the sample stage.

9. The wafer processing apparatus according to any one of claims 6 to 8, wherein, the wafer processing apparatus has a function of achieving either a distribution in which the temperature of the wafer is lower in the central region and higher in the outer peripheral region or a distribution in which the temperature of the wafer is higher in the central region and lower in the outer peripheral region during the processing of the wafer.

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