KR20190098430A - Vapor deposition reactor and a reflector used in the same - Google Patents

Abstract

An embodiment relates to a vapor deposition device which comprises: a reaction furnace; lamps arranged in an upper portion of the reaction furnace to discharge heat; and a first reflector arranged between the lamps to reflect the heat discharged from the lamps. The first reflector comprises: a body extending in a vertical direction; a first reflective unit extending from an outer surface of the body in a horizontal direction, and located between an upper end and a lower end of the body; and a second reflective unit arranged below the first reflective unit. The second reflective unit includes an upper surface facing the body and a lower surface located below the upper surface and facing the reaction furnace. The lower surface of the second reflective unit is an inclination surface inclined with respect to a horizontal surface by a predetermined angle, and the horizontal surface is a surface parallel with the horizontal direction.

Description

Vapor Deposition Apparatus and Reflector for Use {VAPOR DEPOSITION REACTOR AND A REFLECTOR USED IN THE SAME}

Embodiments relate to a vapor deposition apparatus and a reflector used therein.

An epitaxial layer is formed on the surface of a silicon wafer (or silicon single crystal substrate) by the vapor phase growth method to produce a silicon epitaxial wafer. In such a silicon epitaxial wafer, it is important to make the thickness of the epitaxial layer uniform.

Since the growth rate of the epitaxial layer grown on the silicon wafer is affected by temperature, it is important to control the temperature distribution in the radial direction of the silicon wafer in order to improve the uniformity of the thickness of the epitaxial layer. That is, in order to improve the uniformity of the thickness of the epitaxial layer, the deviation of the temperature distribution in the radial direction of the wafer should be small. To this end, the vapor deposition apparatus may include a reflector to uniformly provide a temperature to a wafer located inside the reactor.

The embodiment provides a vapor deposition apparatus and a reflector used therein which can improve the uniformity of the thickness of the epitaxial layer of the epitaxial wafer by having a uniform temperature distribution on the wafer disposed in the reactor.

An embodiment is a reactor; Lamps disposed above the reactor and dissipating heat; And a first reflector disposed between the lamps, the first reflector reflecting heat emitted from the lamps, the first reflector extending in a vertical direction; A first reflector extending in a horizontal direction perpendicular to the vertical direction from an outer surface of the main body and positioned between an upper end and a lower end of the main body; And a second reflector disposed below the first reflector, wherein the second reflector includes an upper surface facing the main body and a lower surface positioned below the upper surface and facing the reaction path. An inclined plane inclined by a predetermined angle with respect to a horizontal plane, and the horizontal plane is a plane parallel to the horizontal direction.

The predetermined angle may be 9 degrees to 30 degrees. Alternatively, the predetermined angle may be 10 degrees to 22 degrees.

The diameter of the second reflector may gradually decrease in the lower surface direction from the upper surface of the second reflector.

The first length of the first reflecting portion in the horizontal direction may be greater than the second length of the second reflecting portion in the horizontal direction. The ratio of the second length and the first length may be 1: 1.5 to 1: 1.8.

The second reflector may have a truncated cone shape.

The vapor deposition apparatus may further include a second reflector disposed around the first reflector and positioned between the lamps and the first reflector.

The second reflector may be disposed at a lower end of the main body, and a lower surface of the second reflector may be located below a lower end of the second reflector.

The first reflector may have a symmetrical shape with respect to the main body.

The main body may have a hollow tube structure, and an opening communicating with the main body may be provided at a center of a lower surface of the second reflector.

Embodiments relate to a reflector used to reflect heat emitted from the lamps in a vapor deposition apparatus comprising a reactor and lamps disposed above the reactor, the reflector comprising: a body extending in a vertical direction; A first reflector extending in a horizontal direction perpendicular to the vertical direction from an outer surface of the main body and positioned between an upper end and a lower end of the main body; And a second reflector disposed below the first reflector, wherein the second reflector includes an upper surface facing the main body and a lower surface positioned below the upper surface and facing the reaction path, and the lower surface of the second reflective portion is a horizontal surface. An inclined plane inclined by a predetermined angle with respect to the horizontal plane may be a plane parallel to the horizontal direction.

According to the embodiment, the uniformity of the radiation heat distribution provided to the reactor may be improved, and the uniformity of the thickness of the epitaxial layer of the epitaxial wafer may be improved.

1 is a sectional view of a vapor deposition apparatus according to an embodiment.
FIG. 2 shows a schematic view of the first reflector shown in FIG. 1.
3A illustrates a simulation result regarding a temperature distribution of a wafer in a reactor according to a first preset angle range of a lower surface of the second reflector.
3B illustrates a simulation result regarding a temperature distribution of a wafer in a reactor according to a second predetermined angle range of a lower surface of the second reflector.
3C illustrates a simulation result regarding a temperature distribution of a wafer in a reactor according to a third predetermined angle range of the bottom surface of the second reflector.
FIG. 4 shows the temperature deviation of the wafer in the reactor according to the first to third preset angular ranges of FIGS. 3A-3C.
FIG. 5 is a graph illustrating an improvement rate in cases where the temperature deviation is improved in FIG. 4.

Hereinafter, the embodiments will be apparent from the accompanying drawings and the description of the embodiments. In the description of an embodiment, each layer (region), region, pattern, or structure is "on" or "under" the substrate, each layer (film), region, pad, or pattern. In the case where it is described as being formed at, "up" and "under" include both "directly" or "indirectly" formed through another layer. do. In addition, the criteria for up / down or down / down each layer will be described with reference to the drawings. Like reference numerals denote like elements throughout the description of the drawings.

1 is a sectional view of a vapor deposition apparatus 100 according to an embodiment.

Referring to FIG. 1, the vapor deposition apparatus 100 is a single-leaf type wafer that processes wafers one by one, and vapor-grows an epitaxial layer on a wafer (or a semiconductor substrate), which is a substrate to be processed. Can be prepared.

The vapor deposition apparatus 100 includes a reactor (or chamber 101), at least one heater 105 (or lamp) for generating heat, and a reflector disposed on the reactor 101 ( Reflector 110 may be provided.

The reactor 105 is a space where an epitaxial reaction occurs and may be made of quartz glass, but is not limited thereto.

Reactor 101 may be in the form of a container including a top, bottom, and side surfaces.

The reactor 101 includes a main body 102, an upper dome (or upper cover 103) positioned on the main body 102, and a lower dome (or lower cover 104) positioned below the main body 102. It may include.

The body 102 may be cylindrical, but is not limited thereto. The main body 102 may include an inlet 3a positioned at one side and an outlet 3b positioned at the other side. Each of the inlet port 3a and the outlet port 3b may be in the form of a passage or a hole communicating from the outside of the body 102 to the inside of the body 102.

The vapor deposition apparatus 100 may further include a first clamp ring 6a that fixes and supports the upper dome 103, and a second clamp ring 6b that fixes and supports the lower dome 104. have.

The vapor deposition apparatus 100 includes a susceptor 7 disposed in the reactor 101, a susceptor support 8 disposed below the susceptor 7 and supporting the susceptor 7, and a susceptor. It may include a driver 9 for driving the susceptor 7 through the support (8). For example, the driver 9 may rotate the susceptor support 8 about the reference axis OA. For example, the reference axis OA may be an axis passing through the center of the reactor 103 and corresponding or aligned with the susceptor support 8.

The susceptor 7 is a portion where the wafer W is loaded during the epitaxial reaction. The susceptor 7 may be formed of carbon graphite, silicon carbide, or carbon carbide coated with silicon carbide, but is not limited thereto.

The vapor deposition apparatus 100 may include a gas supply pipe 10 connected or communicated with the inlet 3a of the main body 101, and a gas discharge pipe 11 connected or communicated with the outlet 3b of the main body 101. Can be.

Source gas may be supplied or introduced into the reactor 101 (or the main body 102) from the gas supply pipe 10 through the inlet port 3a, and the source gas introduced into the reactor 101 may be introduced into the reactor. After flowing along the surface of a wafer (eg, a silicon wafer) located inside the 101, it may be discharged to the gas discharge pipe 11 through the outlet 3b.

In FIG. 1, only one gas supply pipe 10, a gas discharge pipe 11, an inlet port 3a, and an outlet port 3b are illustrated, but the present invention is not limited thereto.

The vapor deposition apparatus 100 includes a case 12 accommodating a reactor 101, a heater 105, a reflector 110, a susceptor 7, and a susceptor support 8 therein. It may further include.

The heater 105 is disposed on at least one of the upper part or the lower part of the reactor 103 and generates heat.

For example, the heaters 105 are disposed above the reactor 103 and spaced apart from each other, and are disposed at least two first lamps 105a and 105b that emit heat, and spaced apart from each other below the reactor 103. And two or more second lamps 105c and 105d that emit heat.

For example, the two or more first lamps 105a and 105b may be disposed radially with respect to the reference axis OA. In addition, the two or more second lamps 105c and 105d may be disposed radially with respect to the reference axis OA.

The reflector 110 is disposed on the reactor 101 and reflects heat (or hot wire) generated from the heater 105 and / or radiant heat generated from the reactor 101. The heat (or hot wire) reflected by the reflector 110 may be irradiated or transferred to the wafer W positioned inside the reactor 101. For example, the reflector 110 may be made of a material that reflects heat.

For example, the reflector 110 may be disposed inside the first lamps 105a and 105b and may be arranged to block the first lamps 105a 105b from each other in the horizontal direction.

The vapor deposition apparatus 100 may further include a reflector disposed under the reactor 101 and disposed inside the second lamps 105c and 105d.

The reflector 110 includes a first reflector 210 and a second reflector 220 disposed around the first reflector 210.

The first reflector 210 is fixed to the top of the case 12 and may be a hollow structure (eg, a cylindrical shape). For example, the first reflector 210 may be aligned or overlapped with the reference axis OA.

The first reflector 210 may serve to secure an optical path of a thermometer (eg, a radiation thermometer (not shown)) that measures the temperature of the wafer W loaded on the susceptor 7.

The second reflector 220 may be disposed around the first reflector 210, may be located between the first lamps 105a and 105b and the first reflector 210, and may be spaced apart from the first reflector 210. It may be disposed and may be a tubular structure (eg, a cylindrical structure) with the top and the bottom open.

The vapor deposition apparatus 100 may be disposed on the first lamps 105a and 105b and further include a support 25 for supporting an upper end of the second reflector 220.

For example, the upper, upper, or upper surface of the second reflector 220 may be located below the upper, upper, or upper surface of the first reflector 210, and the lower, lower, or lower surface of the first reflector 210 may be The lower reflector 220 may be positioned below the lower, lower, or lower surface of the second reflector 220.

For example, a lower end of the second reflector 220 may include a portion 220a that is bent or curved inwardly, but is not limited thereto. In another embodiment, the second reflector 220 may have a lower portion of the second reflector 220. It may not.

The vapor deposition apparatus 100 further includes a cooler 130 disposed outside the case 12 and introducing or introducing cold air into the case 12 through a passage pipe 17, for example, a duct. can do. The cooler 130 may serve to cool the outer wall of the reactor 101 and the reflector 110.

FIG. 2 shows a schematic diagram of the first reflector 210 shown in FIG. 1.

Referring to FIG. 2, the first reflector 210 includes a main body 211, a first reflecting unit 212, a second reflecting unit 213, and a third reflecting unit 214.

The body 211 may be a hollow structure extending in the vertical direction, for example, a hollow cylinder, but is not limited thereto. The vertical direction may be a direction parallel to the reference axis OA.

The body 211 may be disposed inside the first lamps 105a and 105b. For example, the main body 211 may be disposed inside the second reflector 220.

The main body 211 may be disposed to overlap or align with the center or the central area of the reactor in the vertical direction.

The main body 211 may be positioned to overlap or align in a vertical direction with the wafer W on the wafer W disposed on the susceptor 7. For example, the main body 211 may be aligned or overlapped with the reference axis OA, but is not limited thereto.

A passage through which light emitted from a thermometer (eg, a radiation thermometer (not shown)) measuring a temperature of the wafer W may be provided inside the main body 211.

The lower end of the body 211 may be located below the lower end of the second reflector 220. This is to ensure a stable light path of the thermometer, and to distribute the heat more widely.

Alternatively, in another embodiment, the lower end of the main body 211 may be positioned at the same height or lower than the lower end of the second reflector 220.

The first reflector 212 may be disposed between the upper end and the lower end of the main body 211, and may have a plate shape, but is not limited thereto.

For example, the first reflector 212 may have a plate shape extending in a horizontal direction from an outer circumferential surface of the main body 211.

For example, the first reflector 212 may have a disk shape or a ring shape, but is not limited thereto. The horizontal direction may be a direction perpendicular to the reference axis OA.

For example, the first reflector 212 may have a disk shape parallel to the horizontal direction. For uniform heat reflection, the first reflector 212 may have a symmetrical shape with respect to the body 211.

For example, the first reflecting unit 212 may be disposed to overlap the first lamps 105a and 105b in the horizontal direction, but is not limited thereto.

The second reflector 213 is positioned below the first reflector 212 and is fixedly disposed at the lower end of the main body 211. The second reflector 213 is uniformly dispersed in the space SP1 located above the reactor 101 corresponding to the susceptor 7 so that heat transmitted downward from the first reflector 212 may be spread. do.

The lower surface of the second reflector 213 may be located below the lower end of the second reflector 220. For example, the lower surface of the second reflector 213 may be located below the lower end of the bent portion 220a of the second reflector 220.

In addition, the second reflector 213 may extend in the horizontal direction from the lower or lower end of the outer surface of the main body 211, may be a disk or ring shape, but is not limited thereto.

The second reflector 213 has an upper surface 213b facing the first reflector 212, a lower surface 213a positioned below the upper surface 213b, and a side surface connecting the upper surface 213b and the lower surface 213a. 213c.

For example, the upper surface 213b of the second reflector 213 may contact the lower end of the main body 211 and may be flat.

For example, the lower surface 213a of the second reflector 213 may be an inclined surface inclined by a predetermined angle θ based on the horizontal surface 201. For example, the horizontal plane 201 may be a plane parallel to the horizontal direction.

The second reflector 213 may have a structure in which the diameter decreases from the upper side to the lower direction. For example, the second reflector 213 may have a truncated cone shape.

An opening may be provided at the center of the lower surface of the second reflector 213 to connect or communicate with the main body 211.

For example, the inclined surface of the second reflector 213 may be a flat surface, but is not limited thereto. In another embodiment, it may be a curved surface having a constant curvature, for example, a concave surface or a convex surface.

For example, the second reflector 213 may have a symmetrical shape with respect to the body 211.

For example, the lower surface 213a or the inclined surface of the second reflector 9213 may have a symmetrical shape with respect to the main body 211.

When the lower surface 213a of the second reflecting portion 213 is an inclined surface, the heat radiation distribution transmitted to the space SP1 on the upper portion of the reactor 101 can be made uniform, which causes the standing in the reactor 101 to be uniform. It is possible to reduce the deviation of the temperature distribution in the radial direction of the wafer (W) loaded in the receptor (7), thereby ensuring the uniformity and reliability of the quality of the epitaxial wafer (W) manufactured in the reactor (101) can do. For example, according to the second reflector 213, the uniformity of the thickness of the epitaxial layer formed on the epitaxial wafer W may be ensured.

The third reflector 214 may be disposed on the upper portion of the main body 211 and may have a disk shape or a ring shape extending in the horizontal direction, but is not limited thereto. For example, the third reflector 214 may have a flat disc shape, but is not limited thereto.

An upper end of the main body 211 or an upper end of the third reflector 214 may be fixed to the upper or upper end of the case 12, but is not limited thereto.

For example, in order to secure an optical path of the thermometer, each of the first to third reflecting units 212, 213, and 214 may have a structure penetrated by the main body 211.

The first diameter or the first length L1 in the horizontal direction of the first reflector 212 is the second diameter or the second length L2 in the horizontal direction of the upper surface 213b of the second reflector 213. May be greater than (L1> L2).

The first diameter or the first length L1 in the horizontal direction of the first reflector 212 may be smaller than the third diameter or the third length L3 in the horizontal direction of the third reflector 214 (L1). <L3).

For example, the ratio L2: L1 of the second length L2 and the first length L1 may be 1: 1.5 to 1: 1.8. For example, the ratio L2: L1 of the second length L2 and the first length L1 may be 1: 1.65.

For example, the ratio L2: L3 of the second length L2 and the third length L3 may be 1: 2 to 1: 2.5. For example, the ratio L2: L3 may be 1: 2.2.

If the value obtained by dividing the first length L1 by the second length L2 is less than 1.5 or greater than 1.8, the space SP1 is reflected by the first reflector 210 and positioned above the reactor 101. Since the distribution of heat radiated to the substrate is not uniform, the deviation of the temperature distribution in the radial direction of the wafer W loaded on the susceptor 7 may be increased.

3A illustrates a simulation result regarding a temperature distribution of the wafer W in the reactor according to the first predetermined angle range of the lower surface 213a of the second reflector 213, and FIG. 3B illustrates the second reflector 213. Shows a simulation result regarding the temperature distribution of the wafer in the reactor according to the second predetermined angle range of the lower surface, and FIG. 3C shows the temperature of the wafer in the reactor according to the third preset angle range of the lower surface of the second reflector 213. 4 shows the simulation results of the distribution, FIG. 4 shows the temperature deviation of the wafer W in the reactor 101 according to the first to third preset angle ranges of FIGS. 3A to 3C, and FIG. 5 is shown in FIG. 4. It is a graph of the improvement rate of the cases where the temperature deviation is improved (CASE 4 to CASE 6, CASE 7 to CASE 10).

In FIG. 3A to FIG. 3C and FIG. 4, "REF" represents a simulation result when the second reflector 213 of the first reflector 210 is not provided.

In FIGS. 3A to 3C, the X axis represents the distance from the center of the wafer to the edge direction, and the Y axis represents raw data about the temperature of each case CASE1 to CASE13 and the temperature of each case CASE1 to CASE13. It can be divided by the mean.

In FIG. 4, MAX represents the maximum value of the temperature of the wafer W, MIN represents the minimum value of the temperature of the wafer W, and MAX-MIN represents the temperature deviation between the maximum value and the minimum value of the temperature of the wafer W. .

In FIG. 4, the improvement rate may be expressed as a percentage of a value obtained by subtracting the temperature of each case from the temperature of REF by the temperature of each case. For example, the improvement rate represented by X in FIG. 4 may be a case where the improvement rate has a negative value.

The temperature variation of the wafer W when the second reflector 213 of the first reflector 210 is not provided (REF) may be 0.004.

When the predetermined angle θ of the lower surface 213a of the second reflector 213 is 0 degrees to 8 degrees (CASE1 to CASE3), the temperature variation of the wafer increases as compared with REF. In addition, when the predetermined angle θ of the lower surface 213a of the second reflector 213 is 31 degrees to 33 degrees (CASE1 to CASE 13), the temperature variation of the wafer increases as compared with REF.

On the other hand, when the predetermined angle θ of the lower surface 213a of the second reflector 213 is 9 degrees to 11 degrees (CASE4 to CASE 6), the temperature variation of the wafer is reduced compared to REF. When the predetermined angle θ of the lower surface 213a of the second reflector 213 is 22 degrees to 30 degrees (CASE7 to CASE 10), the temperature variation of the wafer decreases as compared to REF.

Radiant heat directed toward the upper portion of the wafer by the heat reflection by the wafer may be reflected by the lower surface 213a of the second reflecting portion 213 into the space SP1 on the upper portion of the reactor 101.

In CASE1 to CASE3, heat radiation reflected by the lower surface 213a of the second reflector 213 may be more concentrated in the center region of the wafer, and the temperature variation of the wafer relative to REF is not improved.

In CASE4 to CASE 6 and CASE 7 to CASE 10, the concentration of heat radiation in the center region of the wafer by the lower surface 213a of the second reflector 213 may be suppressed or alleviated, and thus the temperature of the wafer relative to REF may be reduced. The deviation can be improved.

For example, in CASE4 to CASE 6 and CASE 7 to CASE 10, the temperature variation of the wafer relative to REF may be improved by 1.7% to 25%.

In CASE 11 to CASE 13, the concentration of heat radiation in the center region of the wafer may be suppressed or alleviated by the lower surface 213a of the second reflector 213, but the lower surface 213a of the second reflector 213 may be suppressed. Because of the large angle, thermal radiation towards the edge region of the wafer can also be reduced, which does not improve the temperature variation of the wafer relative to REF.

3A to 3C, 4, and 5, the predetermined angle θ of the lower surface 213a of the second reflector 213 according to the embodiment may be 9 degrees to 30 degrees. As a result, the embodiment can suppress or alleviate the concentration of thermal radiation in the central region of the wafer, and improve the temperature variation of the wafer relative to the REF. That is, the embodiment can obtain a temperature deviation improvement rate of 1.7% to 25% of the REF.

Also, for example, in order to have an improvement rate of 5% or more, the predetermined angle θ of the lower surface 213a of the second reflector 213 according to the embodiment may be 9 degrees to 27.5 degrees.

For example, in order to have an improvement rate of 15% or more, the predetermined angle θ of the lower surface 213a of the second reflector 213 according to the embodiment may be 10 degrees to 22 degrees.

Also, for example, in order to have an improvement rate of 20% or more, the predetermined angle θ of the lower surface 213a of the second reflector 213 according to the embodiment may be 10 degrees to 11 degrees.

Ratio L2 of the second length L2 and the first length L1 of the first reflector 210 according to the embodiment to obtain the temperature deviation improvement rate described in FIGS. 3A to 3C, 4, and 5: L1) may be as described above.

Features, structures, effects, and the like described in the above embodiments are included in at least one embodiment of the present invention, and are not necessarily limited to only one embodiment. Furthermore, the features, structures, effects, and the like illustrated in the embodiments may be combined or modified with respect to other embodiments by those skilled in the art to which the embodiments belong. Therefore, contents related to such combinations and modifications should be construed as being included in the scope of the present invention.

Claims (12)

Reactor;
Lamps disposed above the reactor and dissipating heat; And
A first reflector disposed between the lamps and reflecting heat emitted from the lamps,
The first reflector,
A body extending in the vertical direction;
A first reflector extending in a horizontal direction perpendicular to the vertical direction from an outer surface of the main body and positioned between an upper end and a lower end of the main body; And
A second reflector disposed under the first reflector,
The second reflector includes an upper surface facing the main body and a lower surface positioned below the upper surface and facing the reaction path,
The lower surface of the second reflector is an inclined surface inclined by a predetermined angle with respect to the horizontal plane, the horizontal plane is a plane parallel to the horizontal direction. The method of claim 1,
The predetermined angle is a vapor deposition apparatus of 9 degrees to 30 degrees. The method of claim 1,
The predetermined angle is a vapor deposition apparatus of 10 degrees to 22 degrees. The method of claim 1,
And a diameter of the second reflector gradually decreases from the upper surface of the second reflector toward the lower surface. The method of claim 1,
And a first length of the first reflecting portion in the horizontal direction is greater than a second length of the second reflecting portion in the horizontal direction. The method of claim 5,
The ratio of the second length and the first length is 1: 1.5 to 1: 1.8 vapor deposition apparatus. The method of claim 4, wherein
And the second reflector has a truncated cone shape. The method of claim 1,
And a second reflector disposed around the first reflector and positioned between the lamps and the first reflector. The method of claim 8,
The second reflector is disposed at the lower end of the body,
The lower surface of the second reflector is a vapor deposition apparatus located below the lower end of the second reflector. The method of claim 1,
The first reflector has a symmetrical shape with respect to the body. The method of claim 1,
And the main body has a hollow tube structure, and an opening communicating with the main body is provided at a center of a lower surface of the second reflector. A reflector used to reflect heat emitted from the lamps in a vapor deposition apparatus including a reactor and lamps disposed above the reactor,
A body extending in the vertical direction;
A first reflector extending in a horizontal direction perpendicular to the vertical direction from an outer surface of the main body and positioned between an upper end and a lower end of the main body; And
A second reflector disposed under the first reflector;
The second reflector includes an upper surface facing the main body and a lower surface positioned below the upper surface and facing the reaction path,
The lower surface of the second reflector is an inclined plane inclined by a predetermined angle with respect to a horizontal plane, and the horizontal plane is a plane parallel to the horizontal direction.

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