TWI688007B - Heat treatment method - Google Patents

Abstract

The invention provides a heat treatment device and a heat treatment method capable of accurately measuring the reflectance of a substrate while suppressing pattern dependence.

The light for measuring reflectance emitted from the light projecting section 300 is reflected by the half mirror 236 and irradiated onto the surface of the semiconductor wafer W supported by the rotation supporting section 237. The three light-receiving portions 235a, 235b, and 235c receive the reflected light reflected by the light irradiated from one light-projecting portion 300 at three different locations on the surface of the semiconductor wafer W. The reflectance estimation unit 31 estimates the reflectance of each of the reflection positions of the three parts from the intensity of the light irradiated by the light projecting unit 300 and the intensity of the reflected light received by each of the three light receiving units 235a, 235b, and 235c, and then estimates Its average value. By measuring the reflectance of a plurality of locations, the reflectance of the semiconductor wafer W can be accurately measured while suppressing the pattern dependency.

Description

Heat treatment method

The present invention relates to a heat treatment device and a heat treatment method for heating a thin plate-shaped precision electronic substrate (hereinafter, simply referred to as a "substrate") such as a semiconductor wafer to heat the substrate.

In the manufacturing process of semiconductor devices, flash lamp annealing (FLA, Flash Lamp Anneal) heating semiconductor wafers in a very short time has attracted attention. Flash lamp annealing is a method of irradiating the surface of a semiconductor wafer with a xenon flash lamp (hereinafter, referred to as a "flash lamp" when only set to "flash lamp") to flash the surface of the semiconductor wafer for a very short time (less than a few milliseconds) Heat-up heat treatment technology.

The radiation spectral distribution of the xenon flash lamp is from the ultraviolet region to the near infrared region, the wavelength is shorter than that of the previous halogen lamp, and it is roughly consistent with the basic absorption band of the silicon semiconductor wafer. Thus, when the semiconductor wafer is irradiated with flash light from the xenon flash lamp, the transmitted light is small, and the semiconductor wafer can be rapidly heated. In addition, it has also been found that if the flash irradiation is performed for a very short time of several milliseconds or less, it is possible to selectively raise the temperature only near the surface of the semiconductor wafer.

Such flash lamp annealing is used for processes that must be heated for a very short time, such as the activation of impurities typically implanted into semiconductor wafers. If the surface of the semiconductor wafer with impurities implanted by the ion implantation method is irradiated from the flash lamp, the surface of the semiconductor wafer can be heated to the activation temperature in a very short time, and the impurities will not be diffused deeper. Only impurity activation may be performed.

In the flash lamp annealing, flash irradiation with extremely short irradiation time is performed to instantaneously heat up the semiconductor wafer, so the luminous intensity of the flash lamp cannot be feedback-controlled in real time while measuring the wafer temperature. Therefore, it is necessary to obtain the temperature of the semiconductor wafer surface at the time of flash irradiation by pre-calculation, and adjust the luminous intensity of the flash lamp by heating the surface to a specific target temperature. Patent Literature 1 discloses a technique for measuring the reflectance of a semiconductor wafer to be processed, and estimating the temperature reached by the surface of the semiconductor wafer during flash irradiation based on the reflectance. In the technique disclosed in Patent Document 1, the surface of the semiconductor wafer is irradiated with halogen light from a halogen lamp, and the reflectance of the semiconductor wafer is estimated from the intensity of the reflected light.

[Prior Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2014-45067

However, in many cases, various patterns for element formation are formed on the surface of the semiconductor wafer to be processed. If a plurality of different patterns are formed on the surface of the semiconductor wafer In the case of patterns, there is a problem that the measurement result differs depending on the location of the halogen light for irradiance reflectance measurement, and accurate reflectance cannot be measured.

In addition, for example, in FinFET (Fin Field-Effect Transistor), a three-dimensional pattern is formed on the surface of a semiconductor wafer, and even if the portions are the same, the reflectance varies depending on the direction. That is, the method of measuring the reflectance from the surface of the semiconductor wafer by irradiating light with the intensity of the reflected light has the following problem: the dependence on the pattern is strong, and it is difficult to accurately measure the reflectance.

The present invention has been completed in view of the above-mentioned problems, and an object thereof is to provide a heat treatment apparatus and a heat treatment method that can accurately measure the reflectance of a substrate while suppressing pattern dependency.

In order to solve the above problems, the invention of claim 1 is a heat treatment device that heats the substrate by irradiating the substrate with light. The heat treatment device is characterized by including a heating lamp that irradiates the substrate with light to heat the substrate A rotation support portion, which supports the substrate and rotates it; a light projection portion, which irradiates the portion of the substrate rotated by the rotation support portion except for the center of rotation with light for measuring reflectance; a light receiving portion, which receives The light irradiated from the light projecting part is reflected light reflected by the substrate; and the reflectance estimation part estimates the intensity of the light irradiated from the light projecting part and the intensity of the reflected light received by the light receiving part Reflectivity.

In addition, the invention of claim 2 is the heat treatment device according to claim 1, characterized in that it includes a plurality of light projecting portions, and the distance of the plurality of light projecting portions from the rotation center to the substrate A plurality of different parts are irradiated with light for measuring reflectance.

In addition, the invention of claim 3 is a heat treatment device that heats the substrate by irradiating the substrate with light. The heat treatment device is characterized by including: a heating lamp that irradiates the substrate with light to heat the substrate; A light section that irradiates the substrate with light for measuring reflectance; a plurality of light-receiving sections that receive reflected light reflected by the light emitted from the light-projecting section through a plurality of parts of the substrate; and a reflectance estimation section that The intensity of the light irradiated by the light projecting portion and the intensity of the reflected light received by the plurality of light receiving portions are used to estimate the reflectance of the plurality of portions of the substrate.

Furthermore, the invention of claim 4 is the heat treatment device of the invention of claim 3, wherein the reflectance estimation unit estimates the average reflectance, which is an average value of the reflectances of the plurality of locations.

Furthermore, the invention of claim 5 is the heat treatment device of the invention of claim 3, characterized in that the plurality of parts are adjusted from the heating lamp to the plurality of parts based on the reflectance of the plurality of parts estimated by the reflectance estimating unit. The intensity of the irradiated light.

In addition, the invention of claim 6 is a heat treatment device that heats the substrate by irradiating the substrate with light. The heat treatment device is characterized by including: a heating lamp that irradiates the substrate with light to heat the substrate; A light section that irradiates the substrate with light for measuring reflectance; a plurality of light-receiving sections that receive reflected light reflected by a specific portion of the substrate from light irradiated from the light-projecting section; and a reflectance estimation section that emits light from the above The intensity of the light irradiated by the light projection The intensity of the reflected light received by the several light-receiving parts estimates the reflectance of the specific part of the substrate.

In addition, the invention of claim 7 is a heat treatment method that heats the substrate by irradiating the substrate with light. The heat treatment method is characterized by including a heating step that irradiates the substrate with light from a heating lamp to heat the substrate The substrate; the irradiation step, which irradiates the rotating substrate with a portion other than the center of rotation for measuring reflectance; the light-receiving step, which receives the reflected light reflected by the substrate from the light irradiated in the irradiation step; and The reflectance estimation step is to estimate the reflectance of the substrate from the intensity of the light irradiated in the irradiation step and the intensity of the reflected light received in the light reception step.

Further, the invention of claim 8 is the heat treatment method of the invention of claim 7, characterized in that in the irradiation step, a plurality of parts of the substrate having different distances from the rotation center are irradiated with light for measuring reflectance.

Furthermore, the invention of claim 9 is a heat treatment method which heats the substrate by irradiating the substrate with light. The heat treatment method is characterized by comprising a heating step which irradiates the substrate with light from a heating lamp to heat The substrate; the irradiation step, which irradiates the substrate with light for measuring reflectance; the light reception step, which receives the light reflected by the light irradiated in the irradiation step through a plurality of light-receiving parts through the plurality of parts of the substrate; And a reflectance estimation step, which is to estimate the reflectance of the plurality of parts of the substrate from the intensity of the light irradiated in the irradiation step and the intensity of the reflected light received by the plurality of light receiving parts in the light receiving step.

In addition, the invention of claim 10 is the heat treatment method of the invention of claim 9, characterized in that, in the reflectance estimation step, an average reflectance, which is an average value of the reflectances of the plurality of locations, is estimated.

Further, the invention of claim 11 is the heat treatment method of the invention of claim 9, wherein the plurality of plural lamps from the heating lamp in the heating step are adjusted in accordance with the reflectance of the plurality of parts estimated in the reflectance estimation step The intensity of the light irradiated by the part.

In addition, the invention of claim 12 is a heat treatment method that heats the substrate by irradiating the substrate with light. The heat treatment method is characterized by including a heating step that irradiates the substrate with light from a heating lamp to heat the substrate The substrate; the irradiation step, which irradiates the substrate with light for measuring reflectance; the light reception step, which receives light reflected by the light irradiated in the irradiation step through a plurality of light-receiving parts through a specific portion of the substrate; and The reflectance estimation step is to estimate the reflectance of the specific part of the substrate from the intensity of the light irradiated in the irradiation step and the intensity of the reflected light received by the plurality of light receiving portions in the light receiving step.

According to the inventions of claims 1 and 2, the parts of the rotating substrate other than the center of rotation are irradiated with light for measuring reflectance, so the reflectance of a plurality of parts on the substrate is measured, so that the pattern dependence can be suppressed and the substrate can be accurately measured Of reflectivity.

According to the inventions of technical solutions 3 to 5, the reflectance of the plurality of parts of the substrate is estimated from the intensity of the reflected light reflected from the plurality of parts of the substrate, so the pattern dependence can be suppressed and accurate measurement can be performed Set the reflectivity of the substrate.

In particular, according to the invention of claim 5, the intensity of light irradiated from the self-heating lamp to the plurality of parts is adjusted according to the estimated reflectances of the plurality of parts, so that the temperature distribution in the plane of the substrate can be made uniform.

According to the invention of technical solution 6, the reflectance of a specific part of the substrate is estimated from the intensity of a plurality of reflected lights after being reflected by the specific part of the substrate, so the scattering component of the specific part can also be measured, and the pattern dependence can be suppressed and accurate Measure the reflectance of the substrate.

According to the inventions of claims 7 and 8, the parts of the rotating substrate other than the center of rotation are irradiated with light for measuring reflectance, so the reflectance of a plurality of parts on the substrate is measured, so that the pattern dependence can be suppressed and the substrate can be accurately measured Of reflectivity.

According to the inventions of technical solutions 9 to 11, the reflectance of the plurality of parts of the substrate is estimated from the intensity of the reflected light reflected from the plurality of parts of the substrate, so that the reflectivity of the substrate can be accurately measured while suppressing the pattern dependency.

In particular, according to the invention of claim 11, the intensity of light irradiated from the self-heating lamp to the plurality of parts is adjusted according to the estimated reflectance of the plurality of parts, so that the temperature distribution in the plane of the substrate can be made uniform.

According to the invention of technical solution 12, a plurality of reflections after being reflected from a specific part of the substrate The intensity of light estimates the reflectance of a specific part of the substrate, so the scattering component of the specific part can also be measured, and the reflectivity of the substrate can be accurately measured by suppressing the pattern dependency.

3: Control Department

4: Halogen light box

5: flash box

6: processing chamber

7: Holding Department

10: Transfer mechanism

11: Transfer arm

12: jack up

13: Horizontal moving mechanism

14: Lifting mechanism

20: Radiation thermometer

31: Reflectance estimation department

41: Shell

43: reflector

51: Shell

52: reflector

53: Light radiation window

61: Side of chamber

62: recess

63: upper chamber window

64: Lower chamber window

65: heat treatment space

66: Transport opening

68: reflection ring

69: reflection ring

71: Abutment ring

72: Connection Department

74: crystal seat

75: holding plate

75a: keep the surface

76: Guide ring

77: substrate support pin

78: opening

79: through hole

81: gas supply hole

82: buffer space

83: gas supply pipe

84: Valve

85: Process gas supply source

86: gas vent

87: buffer space

88: gas exhaust pipe

89: Valve

100: heat treatment device

101: Indexer Department

110: load port

120: handover robot

120R: Arrow

120S: Arrow

121: Manipulator

130: Cooling Department

131: 1st cold room

140: Cooling Department

141: Second cold room

150: transport robot

150R: Arrow

151a: Transport robot

151b: Transport robot

155: oxygen concentration meter

160: Heat Treatment Department

170: transfer chamber

181: Gate valve

182: Gate valve

183: Gate valve

184: Gate valve

185: Gate valve

190: Exhaust mechanism

191: Gas exhaust pipe

192: Valve

230: Alignment

231: Align chamber

232: Reflectance measurement section

235: Light receiving department

235a: Light receiving department

235b: Light receiving department

235c: Light receiving department

236: Half mirror

237: Rotating support

238: Rotating motor

300: Projection Department

301: Area

C: Vehicle

CU: arrow

FL: Flash

HL: Halogen lamp

W: Semiconductor wafer

FIG. 1 is a plan view showing the heat treatment apparatus of the present invention.

Fig. 2 is a front view of the heat treatment apparatus of Fig. 1.

3 is a longitudinal cross-sectional view showing the structure of the heat treatment section.

4 is a perspective view showing the overall appearance of the holding portion.

Figure 5 is a top view of the crystal base.

Figure 6 is a cross-sectional view of the crystal base.

7 is a top view of the transfer mechanism.

8 is a side view of the transfer mechanism.

9 is a plan view showing the arrangement of a plurality of halogen lamps.

FIG. 10 is a diagram showing the configuration of the reflectance measuring unit.

FIG. 11 is a diagram schematically showing a reflectance measurement area in the first embodiment.

FIG. 12 is a diagram showing the configuration of a reflectance measuring unit in the second embodiment.

Fig. 13 is a diagram showing the configuration of a reflectance measuring unit in a third embodiment.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

<First Embodiment>

300mm或

450mm，但並無特別限定。於搬入至熱處理裝置100之前之半導體晶圓W中注入有雜質，藉由熱處理裝置100之加熱處理而執行所注入之雜質之活化處理。再者，於圖1及其後之各圖中，為了容易理解，視需要而對各部之尺寸或數量進行誇大或簡化地描繪。又，於圖1~圖3之各圖中，為了明確其等之方向關係，標有將Z軸方向設為鉛直方向、且將XY平面設為水平面之XYZ正交座標系。 First, the overall structure of the heat treatment apparatus 100 of the present invention will be described. FIG. 1 is a plan view showing the heat treatment apparatus 100 of the present invention, and FIG. 2 is a front view thereof. The heat treatment apparatus 100 is a flash lamp annealing apparatus that irradiates a semiconductor wafer W having a circular plate shape as a substrate with a flash to heat the semiconductor wafer W. The size of the semiconductor wafer W to be processed is, for example,

300mm or

450mm, but not particularly limited. Impurities are implanted into the semiconductor wafer W before being carried into the heat treatment apparatus 100, and the activation treatment of the implanted impurities is performed by the heat treatment of the heat treatment apparatus 100. In addition, in FIG. 1 and subsequent figures, the size or number of each part is exaggerated or simplified as necessary for easy understanding. In addition, in each of FIGS. 1 to 3, in order to clarify the directional relationship, an XYZ orthogonal coordinate system in which the Z axis direction is the vertical direction and the XY plane is the horizontal plane is indicated.

As shown in FIGS. 1 and 2, the heat treatment apparatus 100 includes an indexer section 101 for carrying unprocessed semiconductor wafers W into the apparatus from the outside, and carrying the processed semiconductor wafers W out of the apparatus; Alignment part 230, which positions the unprocessed semiconductor wafer W; two cooling parts 130, 140, etc., which cool the semiconductor wafer W after heat treatment; heat treatment part 160, which implements the semiconductor wafer W Flash heat treatment; and a transfer robot 150, which transfers the semiconductor wafers W to the cooling sections 130, 140 and the heat treatment section 160. In addition, the heat treatment apparatus 100 includes a control unit 3 that controls the operating mechanism and the transport robot 150 provided in the above-described processing units to perform flash heating processing of the semiconductor wafer W.

The indexer section 101 includes: a load port 110 that places a plurality of carriers C (two in the present embodiment) side by side; and a transfer robot 120 that takes out unprocessed semiconductor wafers W from each carrier C and will The processed semiconductor wafer W is stored in each carrier C. The carrier C containing the unprocessed semiconductor wafer W is placed on the load port by being transported by an unmanned transfer vehicle (AGV, OHT), etc. 110, and the carrier C that houses the processed semiconductor wafer W is removed from the load port 110 by an unmanned transfer vehicle.

In addition, at the load port 110, the carrier C is configured such that the transfer robot 120 can move any semiconductor wafer W in and out of the carrier C as shown by the arrow CU in FIG. 2. Furthermore, as the form of the carrier C, in addition to storing the semiconductor wafer W in a closed space FOUP (front opening unified pod, front opening wafer cassette), it can also be SMIF (Standard Mechanical Inter Face, standard mechanical interface) ) Box or an OC (open cassette) that exposes the stored semiconductor wafer W to outside air.

In addition, the transfer robot 120 can perform a sliding movement as shown by an arrow 120S in FIG. 1, a turning movement as shown by an arrow 120R, and a lifting operation. As a result, the transfer robot 120 transfers the semiconductor wafer W to and from the two carriers C, and transfers the semiconductor wafer W to the alignment unit 230 and the two cooling units 130 and 140. The transfer of the semiconductor wafer W relative to the carrier C by the transfer robot 120 is performed by the sliding movement of the robot 121 and the lifting movement of the carrier C. In addition, the transfer of the semiconductor wafer W by the transfer robot 120 and the alignment part 230 or the cooling parts 130 and 140 is performed by the sliding movement of the manipulator 121 and the lifting movement of the transfer robot 120.

The alignment portion 230 is connected to the side of the indexer portion 101 along the Y-axis direction. The alignment portion 230 is a processing portion that rotates the semiconductor wafer W in a horizontal plane toward a direction suitable for flash heating. In the alignment part 230, inside the alignment chamber 231 which is a case made of aluminum alloy, a mechanism for supporting and rotating the semiconductor wafer W in a horizontal posture is provided (rotation support part 237, rotation motor of FIG. 10) 238), and optically detect the groove formed in the peripheral portion of the semiconductor wafer W Or an orientation flat, etc. In addition, the alignment chamber 231 is provided with a reflectance measuring section 232 that measures the reflectance of the surface of the semiconductor wafer W supported inside. The reflectance measuring unit 232 irradiates the surface of the semiconductor wafer W with light, receives the reflected light reflected by the surface, and measures the reflectance of the surface of the semiconductor wafer W from the intensity of the reflected light. The configuration of the reflectance measuring unit 232 will be described later.

The transfer of the semiconductor wafer W to the alignment part 230 is performed by the transfer robot 120. The delivery of the semiconductor wafer W from the transfer robot 120 to the alignment chamber 231 is performed in such a manner that the center of the wafer is located at a specific position. In the alignment part 230, the center part of the semiconductor wafer W received from the indexer part 101 is used as the rotation center to rotate the semiconductor wafer W around the vertical axis, optically detect the groove, etc., thereby adjusting the orientation of the semiconductor wafer W . In addition, the reflectance measuring unit 232 measures the reflectance of the surface of the semiconductor wafer W. The semiconductor wafer W after the orientation adjustment is taken out of the alignment chamber 231 by the transfer robot 120.

As the transfer space in which the transfer robot 150 transfers the semiconductor wafer W, a transfer chamber 170 accommodating the transfer robot 150 is provided. The processing chamber 6 of the heat treatment section 160, the first refrigerating chamber 131 of the cooling section 130, and the second refrigerating chamber 141 of the cooling section 140 are connected to the three surfaces of the transfer chamber 170.

The heat treatment unit 160, which is the main part of the heat treatment apparatus 100, is a substrate processing unit that irradiates the pre-heated semiconductor wafer W with a flash light from a xenon flash lamp FL to perform flash heat treatment.

The two cooling units 130 and 140 have substantially the same configuration. The cooling units 130 and 140 are respectively equipped with a metal cooling plate and a quartz plate placed on the upper surface of the first refrigerator compartment 131 and the second refrigerator compartment 141, which are made of aluminum alloy casings (both not shown) ). The cooling plate is adjusted to normal temperature (approximately 23°C) by Peltier element or constant temperature water circulation. The semiconductor wafer W subjected to the flash heat treatment by the heat treatment unit 160 is carried into the first refrigerator compartment 131 or the second refrigerator compartment 141 and placed on the quartz plate to be cooled.

Both the first refrigerator compartment 131 and the second refrigerator compartment 141 are connected between the indexer unit 101 and the transfer chamber 170 and both. In the first refrigerator compartment 131 and the second refrigerator compartment 141, two openings for carrying semiconductor wafers W in and out are provided in conformity with shapes. Of the two openings of the first refrigerator compartment 131, the opening connected to the indexer portion 101 can be opened and closed by the gate valve 181. On the other hand, the opening of the first refrigerator compartment 131 connected to the transfer chamber 170 can be opened and closed by the gate valve 183. That is, the first refrigerator compartment 131 and the indexer unit 101 are connected via the gate valve 181, and the first refrigerator compartment 131 and the transfer chamber 170 are connected via the gate valve 183.

When the semiconductor wafer W is transferred between the indexer portion 101 and the first refrigerator compartment 131, the gate valve 181 is opened. In addition, when the semiconductor wafer W is transferred between the first refrigerator compartment 131 and the transfer chamber 170, the gate valve 183 is opened. When the gate valve 181 and the gate valve 183 are closed, the inside of the first refrigerator compartment 131 becomes a sealed space.

In addition, among the two openings of the second refrigerator compartment 141, the opening connected to the indexer portion 101 can be opened and closed by the gate valve 182. On the other hand, the opening of the second refrigerator compartment 141 connected to the transfer chamber 170 can be opened and closed by the gate valve 184. That is, the second refrigerator compartment 141 and the indexer unit 101 pass through the gate valve 182 In addition, the second refrigerator compartment 141 and the transfer chamber 170 are connected via the gate valve 184.

When the semiconductor wafer W is transferred between the indexer unit 101 and the second refrigerator compartment 141, the gate valve 182 is opened. In addition, when the semiconductor wafer W is transferred between the second refrigerator compartment 141 and the transfer chamber 170, the gate valve 184 is opened. When the gate valve 182 and the gate valve 184 are closed, the inside of the second refrigerator compartment 141 becomes a sealed space.

Furthermore, the cooling units 130 and 140 respectively include a gas supply mechanism that supplies purified nitrogen gas to the first refrigerator compartment 131 and the second refrigerator compartment 141, and an exhaust mechanism that exhausts the ambient gas in the chamber. The gas supply mechanism and the exhaust mechanism may be configured to switch the flow rate to two stages.

The transfer robot 150 provided in the transfer chamber 170 can rotate around the axis in the vertical direction as indicated by the arrow 150R. The transfer robot 150 has two link mechanisms including a plurality of arm sections, and transfer robots 151a and 151b holding semiconductor wafers W are provided at the front ends of the two link mechanisms. The transport robots 151a and 151b are arranged at a certain distance from top to bottom, and can be linearly moved independently in the same horizontal direction by a link mechanism. In addition, the transport robot 150 moves up and down the two transport robots 151a and 151b in a state where they are separated by a certain pitch by moving the base provided with the two link mechanisms up and down.

When the transfer robot 150 transfers (in and out) the semiconductor wafer W using the processing chamber 6 of the first refrigerator compartment 131, the second refrigerator compartment 141, or the heat treatment unit 160 as the transfer target, first, the two transfer robots 151a, 151b Swivel in a manner opposed to the transfer target, and then move up and down (or during the rotation), any transport robot is located at the height of the semiconductor wafer W that is transferred to the transfer target degree. Then, the transfer robot 151a (151b) linearly slides in the horizontal direction to transfer the semiconductor wafer W with the transfer target.

The transfer of the semiconductor wafer W by the transfer robot 150 and the transfer robot 120 can be performed via the cooling units 130 and 140. That is, the first refrigerating compartment 131 of the cooling unit 130 and the second refrigerating compartment 141 of the cooling unit 140 also function as a path for transferring the semiconductor wafer W between the transfer robot 150 and the transfer robot 120. Specifically, the semiconductor wafer W is transferred by receiving the semiconductor wafer W delivered to the first refrigerator compartment 131 or the second refrigerator compartment 141 by one of the transfer robot 150 or the transfer robot 120.

As described above, the gate valves 181 and 182 are provided between the first refrigerator compartment 131 and the second refrigerator compartment 141 and the indexer unit 101, respectively. In addition, gate valves 183 and 184 are provided between the transfer chamber 170 and the first refrigerator compartment 131 and the second refrigerator compartment 141, respectively. Furthermore, a gate valve 185 is provided between the transfer chamber 170 and the processing chamber 6 of the heat treatment unit 160. When the semiconductor wafer W is transferred in the heat treatment apparatus 100, the gate valves are appropriately opened and closed.

In addition, an oxygen concentration meter 155 (FIG. 2) is provided inside the transfer chamber 170. The oxygen concentration meter 155 measures the oxygen concentration in the transfer chamber 170. Furthermore, in both the transfer chamber 170 and the alignment chamber 231, nitrogen gas is supplied from the gas supply section, and the internal atmosphere gas and the like are exhausted by the exhaust section (both not shown).

Next, the configuration of the heat treatment unit 160 will be described. FIG. 3 is a longitudinal cross-sectional view showing the structure of the heat treatment section 160. The heat treatment unit 160 includes: a processing chamber 6 that accommodates and advances the semiconductor wafer W Heat treatment; flash box 5, which has a plurality of built-in flashes FL; and halogen light box 4, which has a plurality of built-in halogen lamps HL. A flash lamp box 5 is provided on the upper side of the processing chamber 6, and a halogen lamp box 4 is provided on the lower side. In addition, the heat treatment unit 160 includes: a holding unit 7 that holds the semiconductor wafer W in the processing chamber 6 in a horizontal posture; and a transfer mechanism 10 that performs the semiconductor wafer between the holding unit 7 and the transfer robot 150 W handover.

The processing chamber 6 is configured by attaching a quartz chamber window to the cylindrical chamber side portion 61 above and below. The chamber side portion 61 has a substantially cylindrical shape that opens up and down, and the upper chamber window 63 is attached to the upper opening and closed, and the lower chamber window 64 is attached to the lower opening and closed. The upper chamber window 63 constituting the top wall of the processing chamber 6 is a disc-shaped member formed of quartz, and functions as a quartz window that transmits the flash light emitted from the flash lamp FL into the processing chamber 6. In addition, the lower chamber window 64 that constitutes the bottom wall portion of the processing chamber 6 is also a disc-shaped member formed of quartz, and functions as a quartz window that transmits light from the halogen lamp HL into the processing chamber 6 Features.

In addition, a reflection ring 68 is attached to the upper part of the inner wall surface of the chamber side 61, and a reflection ring 69 is attached to the lower part. The reflection rings 68 and 69 are both formed in a circular ring shape. The upper reflection ring 68 is installed by being fitted from the upper side of the chamber side 61. On the other hand, the lower reflection ring 69 is fitted by being fitted from the lower side of the chamber side 61 and fixed with screws not shown. That is, both the reflection rings 68 and 69 are detachably attached to the chamber side 61. The inner space of the processing chamber 6, that is, the space surrounded by the upper chamber window 63, the lower chamber window 64, the chamber side 61 and the reflection rings 68 and 69 is defined as the heat treatment space 65.

It is formed on the inner wall surface of the processing chamber 6 by installing the reflection rings 68, 69 on the chamber side portion 61 The recess 62. That is, a concave portion 62 surrounded by the central portion of the inner wall surface of the chamber side portion 61 where the reflection rings 68 and 69 are not mounted, the lower end surface of the reflection ring 68, and the upper end surface of the reflection ring 69 is formed. The concave portion 62 is formed in an annular shape on the inner wall surface of the processing chamber 6 in the horizontal direction, and surrounds the holding portion 7 that holds the semiconductor wafer W. The chamber side portion 61 and the reflection rings 68 and 69 are formed of a metal material (for example, stainless steel) excellent in strength and heat resistance.

In addition, the chamber side portion 61 is provided with a transport opening (furnace opening) 66 for carrying in and out the semiconductor wafer W to and from the processing chamber 6 in conformity with the shape. The transfer opening 66 can be opened and closed by the gate valve 185. The transport opening 66 is connected to the outer peripheral surface of the recess 62. Therefore, when the gate valve 185 opens the transport opening 66, the semiconductor wafer W can be carried into the heat treatment space 65 through the recess 62 from the transport opening 66 and the semiconductor wafer W can be carried out from the heat treatment space 65. In addition, when the gate valve 185 closes the conveyance opening 66, the heat treatment space 65 in the processing chamber 6 is set as a closed space.

In addition, a gas supply hole 81 for supplying the processing gas to the heat treatment space 65 is provided in a shape matching the upper portion of the inner wall of the processing chamber 6. The gas supply hole 81 is provided at a higher position than the concave portion 62 in a matching shape, or may be provided at the reflection ring 68. The gas supply hole 81 is communicated and connected to the gas supply pipe 83 via a buffer space 82 formed annularly inside the side wall of the processing chamber 6. The gas supply pipe 83 is connected to the processing gas supply source 85. In addition, a valve 84 is interposed in the middle of the path of the gas supply pipe 83. When the valve 84 is opened, the processing gas is fed from the processing gas supply source 85 to the buffer space 82. The processing gas flowing into the buffer space 82 flows through the buffer space 82 having a smaller fluid resistance than the gas supply hole 81, and is supplied into the heat treatment space 65 from the gas supply hole 81. As the processing gas, an inert gas such as nitrogen (N ₂ ) or a reactive gas (nitrogen in this embodiment) such as hydrogen (H ₂ ) or ammonia (NH ₃ ) can be used.

On the other hand, a gas exhaust hole 86 for exhausting the gas in the heat treatment space 65 is provided in a shape matching the lower part of the inner wall of the processing chamber 6. The gas exhaust hole 86 is provided at a lower position than the concave portion 62 in a matching shape, and may also be provided at the reflection ring 69. The gas exhaust hole 86 is an exhaust pipe 88 formed in a buffer space 87 formed inside the side wall of the processing chamber 6 in an annular shape. The gas exhaust pipe 88 is connected to the exhaust mechanism 190. In addition, a valve 89 is inserted in the middle of the path of the gas exhaust pipe 88. When the valve 89 is opened, the gas in the heat treatment space 65 is discharged from the gas exhaust hole 86 to the gas exhaust pipe 88 via the buffer space 87. Furthermore, the gas supply hole may be connected to the gas 81 and the gas exhaust hole 86 in a plurality along the circumferential direction of the processing chamber 6, or may be slit-shaped. In addition, the processing gas supply source 85 and the exhaust mechanism 190 may be a mechanism provided in the heat treatment apparatus 100, or may be an entity of a factory in which the heat treatment apparatus 100 is installed.

Also, a gas exhaust pipe 191 that exhausts the gas in the heat treatment space 65 is connected to the front end of the transport opening 66. The gas exhaust pipe 191 is connected to the exhaust mechanism 190 via the valve 192. By opening the valve 192, the gas in the processing chamber 6 is discharged through the transport opening 66.

FIG. 4 is a perspective view showing the overall appearance of the holding portion 7. The holding portion 7 is configured by including an abutment ring 71, a coupling portion 72, and a pedestal 74. The abutment ring 71, the connecting portion 72, and the crystal base 74 are all formed of quartz. That is, the entire holding portion 7 is formed of quartz.

The abutment ring 71 is an arc-shaped quartz member formed by missing a part of the ring shape. This missing part is to prevent interference between the transfer arm 11 of the transfer mechanism 10 and the abutment ring 71 described below Settings. The abutment ring 71 is supported on the wall surface of the processing chamber 6 by being placed on the bottom surface of the recess 62 (see FIG. 3 ). On the upper surface of the base ring 71, a plurality of connecting parts 72 (four in the present embodiment) are erected along the circumferential direction of the circular ring shape. The connecting portion 72 is also a member of quartz, and is fixed to the abutment ring 71 by welding.

The pedestal 74 is supported by four connecting portions 72 provided on the abutment ring 71. FIG. 5 is a top view of the crystal base 74. 6 is a cross-sectional view of the pedestal 74. The crystal base 74 includes a holding plate 75, a guide ring 76, and a plurality of substrate support pins 77. The holding plate 75 is a substantially circular flat plate member formed of quartz. The diameter of the holding plate 75 is larger than the diameter of the semiconductor wafer W. That is, the holding plate 75 has a larger plane size than the semiconductor wafer W.

300mm之情形時，引導環76之內徑為

320mm。引導環76之內周設為自保持板75朝上方變寬之錐面。引導環76係由與保持板75相同之石英形成。引導環76可熔接於保持板75之上表面，亦可由另行加工而成之銷等固定於保持板75。或者，亦可將保持板75與引導環76加工成一體之構件。 A guide ring 76 is provided on a peripheral portion of the upper surface of the holding plate 75. The guide ring 76 is a ring-shaped member having an inner diameter larger than the diameter of the semiconductor wafer W. For example, the diameter of the semiconductor wafer W is

In the case of 300mm, the inner diameter of the guide ring 76 is

320mm. The inner circumference of the guide ring 76 is a tapered surface that widens upward from the holding plate 75. The guide ring 76 is formed of the same quartz as the holding plate 75. The guide ring 76 may be welded to the upper surface of the holding plate 75, or may be fixed to the holding plate 75 by a separately processed pin or the like. Alternatively, the holding plate 75 and the guide ring 76 may be processed as an integral member.

300mm，則該直徑為

270mm~

280mm(本實施形態中為

270mm)。各個基板支持銷77係由石英形成。複數個基板支持銷77可藉由熔接而設置於保持板75之上表面，亦可與保持板75加工成一體。 A region of the upper surface of the holding plate 75 that is more inside than the guide ring 76 is a flat holding surface 75 a that holds the semiconductor wafer W. A plurality of substrate support pins 77 are erected on the holding surface 75a of the holding plate 75. In the present embodiment, a total of 12 substrate support pins 77 are erected every 30° along a circumference concentric with the outer circumference of the holding surface 75a (the inner circumference of the guide ring 76). The diameter of the circle formed by 12 substrate support pins 77 (the distance between the opposing substrate support pins 77) is smaller than the diameter of the semiconductor wafer W, if the diameter of the semiconductor wafer W is

300mm, the diameter is

270mm~

280mm (in this embodiment is

270mm). Each substrate support pin 77 is made of quartz. The plurality of substrate support pins 77 may be provided on the upper surface of the holding plate 75 by welding, or may be processed integrally with the holding plate 75.

Returning to FIG. 4, the four connecting portions 72 erected on the abutment ring 71 and the peripheral edge portion of the holding plate 75 of the pedestal 74 are fixed by welding. That is, the base 74 and the abutment ring 71 are fixedly connected by the connecting portion 72. By supporting the abutment ring 71 of such a holding portion 7 on the wall surface of the processing chamber 6, the holding portion 7 is attached to the processing chamber 6. In a state where the holding portion 7 is installed in the processing chamber 6, the holding plate 75 of the pedestal 74 takes a horizontal posture (posture where the normal line coincides with the vertical direction). That is, the holding surface 75a of the holding plate 75 becomes a horizontal plane.

The semiconductor wafer W carried into the processing chamber 6 is placed in a horizontal posture and held on the pedestal 74 of the holding portion 7 mounted in the processing chamber 6. At this time, the semiconductor wafer W is supported by the twelve substrate support pins 77 erected on the holding plate 75 and held on the pedestal 74. More strictly speaking, the upper end portions of the twelve substrate support pins 77 contact the lower surface of the semiconductor wafer W to support the semiconductor wafer W. Since the height of the twelve substrate support pins 77 (the distance from the upper end of the substrate support pin 77 to the holding surface 75a of the holding plate 75) is uniform, the semiconductor wafer W can be supported in a horizontal posture by the twelve substrate support pins 77.

In addition, the semiconductor body wafer W is supported by a plurality of substrate support pins 77 from the holding surface 75a of the holding plate 75 at specific intervals. The thickness of the guide ring 76 compared to the height of the substrate support pin 77 Bigger. Therefore, the positional deviation in the horizontal direction of the semiconductor wafer W supported by the plurality of substrate support pins 77 is prevented by the guide ring 76.

As shown in FIGS. 4 and 5, an opening 78 is formed through the holding plate 75 of the pedestal 74 so as to penetrate vertically. The opening 78 is provided for the radiation thermometer 20 (see FIG. 3) to receive radiation (infrared light) radiated from the lower surface of the semiconductor wafer W held on the pedestal 74. That is, the radiation thermometer 20 receives light radiated from the lower surface of the semiconductor wafer W held on the pedestal 74 through the opening 78, and measures the temperature of the semiconductor wafer W by a separately provided detector. Furthermore, on the holding plate 75 of the pedestal 74, four through-holes 79 through which jack pins 12 of the transfer mechanism 10 described below are penetrated are provided through holes for the delivery of the semiconductor wafer W.

FIG. 7 is a top view of the transfer mechanism 10. 8 is a side view of the transfer mechanism 10. The transfer mechanism 10 includes two transfer arms 11. The transfer arm 11 is shaped like an arc along a substantially circular recess 62. Two lifting pins 12 are erected on each transfer arm 11. Each transfer arm 11 is set to be rotatable by the horizontal movement mechanism 13. The horizontal movement mechanism 13 causes the pair of transfer arms 11 to be transferred from the holding portion 7 to the transfer operation position (solid line position in FIG. 7) of the semiconductor wafer W, and is not held by the holding portion 7 in plan view. The semiconductor wafers W horizontally move between overlapping retreat positions (two-dot chain line position in FIG. 7 ). As the horizontal movement mechanism 13, each transfer arm 11 can be individually rotated by a separate motor, or a pair of transfer arms 11 can be rotated in conjunction with one motor using a link mechanism.

In addition, the pair of transfer arms 11 are moved up and down together with the horizontal movement mechanism 13 by the up and down mechanism 14. If the lifting mechanism 14 raises the pair of transfer arms 11 at the transfer operation position, a total of 4 tops The lifting pin 12 is provided in the through hole 79 (see FIGS. 4 and 5) of the pedestal 74 through perforations, and the upper end of the lifting pin 12 protrudes from the upper surface of the pedestal 74. On the other hand, if the lifting mechanism 14 lowers the pair of transfer arms 11 at the transfer operation position, the jacking pin 12 is pulled out from the through hole 79, and the horizontal movement mechanism 13 moves the pair of transfer arms 11 in an open manner , Each transfer arm 11 moves to the retreat position. The retreat position of the pair of transfer arms 11 is directly above the abutment ring 71 of the holding portion 7. Since the base ring 71 is placed on the bottom surface of the recess 62, the retreat position of the transfer arm 11 becomes the inside of the recess 62. In addition, an exhaust mechanism (not shown) is provided near the portion where the driving portion of the transfer mechanism 10 (the horizontal movement mechanism 13 and the elevating mechanism 14) is provided, and the atmosphere surrounding the drive portion of the transfer mechanism 10 is configured It is discharged to the outside of the processing chamber 6.

Returning to FIG. 3, the flash lamp box 5 provided above the processing chamber 6 is provided with a light source including a plurality of (30 in this embodiment) xenon flash lamp FL inside the housing 51, and in a manner to cover the light source above The reflector 52 is provided. In addition, a light radiation window 53 is installed at the bottom of the housing 51 of the flash box 5. The light radiation window 53 constituting the bottom wall portion of the flash box 5 is a plate-shaped quartz window formed of quartz. By placing the flashlight box 5 above the processing chamber 6, the light radiation window 53 is opposed to the upper chamber window 63. The flash lamp FL irradiates the heat treatment space 65 through the light radiation window 53 and the upper chamber window 63 from above the processing chamber 6.

The plurality of flash lamps FL are respectively rod-shaped lamps having a long cylindrical shape, and are parallel to each other along the main surface (that is, along the horizontal direction) of the semiconductor wafer W held in the holding portion 7 in their respective longitudinal directions The way is arranged in a plane. Therefore, the plane formed by the arrangement of the flash lamps FL is also a horizontal plane.

The xenon flash lamp FL includes: a rod-shaped glass tube (discharge tube) in which xenon gas is enclosed, and an anode and a cathode connected to a capacitor are arranged at both ends of the glass tube; and a trigger electrode is attached to the The outer surface of the glass tube. Since xenon gas is an electrical insulator, even if a charge is stored in the capacitor, current does not flow in the glass tube in the normal state. However, when a high voltage is applied to the trigger electrode to break the insulation, the electricity stored in the capacitor instantly flows in the glass tube, and light is emitted by the excitation of xenon atoms or molecules. In such a xenon flash lamp FL, the electrostatic energy accumulated in the capacitor in advance is converted into an extremely short light pulse of 0.1 ms to 100 ms, so it has a strong intensity compared with a light source that is continuously lit like a halogen lamp HL Characteristics of light. That is, the flash lamp FL is a pulse light emitting lamp that emits light instantly in an extremely short time of less than 1 second. Furthermore, the lighting time of the flash lamp FL can be adjusted according to the coil constant of the lamp power supply that supplies power to the flash lamp FL.

In addition, the reflector 52 is provided above the plurality of flash lamps FL so as to cover the entirety thereof. The basic function of the reflector 52 is to reflect the flash light emitted from the plurality of flash lamps FL toward the side of the heat treatment space 65. The reflector 52 is formed of an aluminum alloy plate, and its surface (the surface facing the side of the flash lamp FL) is roughened by sandblasting.

The halogen lamp box 4 provided below the processing chamber 6 contains a plurality of (40 in this embodiment) halogen lamps HL inside the housing 41. A plurality of halogen lamps HL irradiate the heat treatment space 65 from below the processing chamber 6 through the lower chamber window 64.

9 is a plan view showing the arrangement of a plurality of halogen lamps HL. In the present embodiment, 20 halogen lamps HL are arranged in each of the upper and lower stages. Each halogen lamp HL has a long cylindrical shape Rod lights. The 20 halogen lamps HL in the upper and lower stages are arranged in such a manner that their longitudinal directions are parallel to each other along the main surface (that is, along the horizontal direction) of the semiconductor wafer W held by the holding portion 7. Therefore, the upper and lower sections are formed by the arrangement of the halogen lamps HL as a horizontal plane.

Furthermore, as shown in FIG. 9, the arrangement density of the halogen lamps HL in the upper section and the lower section is higher than the area opposed to the central portion of the semiconductor wafer W held in the holding portion 7 and the area opposed to the peripheral portion high. In other words, the upper and lower sections are the central part of the lamp arrangement, and the arrangement interval of the halogen lamps HL in the peripheral part is shorter. Therefore, when heating is performed by the light irradiation from the halogen lamp HL, the peripheral portion of the semiconductor wafer W that is likely to have a lowered temperature can be irradiated with a larger amount of light.

In addition, the lamp group including the halogen lamp HL in the upper stage and the lamp group including the halogen lamp HL in the lower stage are arranged in a grid-like manner. That is, a total of 40 halogen lamps HL are arranged in such a manner that the longitudinal direction of each halogen lamp HL in the upper stage is orthogonal to the longitudinal direction of each halogen lamp HL in the lower stage.

The halogen lamp HL is a filament-type light source that emits light by incising the filament by energizing the filament arranged inside the glass tube. Inside the glass tube, a gas in which a trace amount of halogen elements (iodine, bromine, etc.) is introduced into an inert gas such as nitrogen or argon is enclosed. By introducing halogen elements, it is possible to suppress the breakage of the filament, and set the temperature of the filament to a high temperature. Therefore, the halogen lamp HL has a characteristic that it has a longer life and can irradiate stronger light continuously than a conventional incandescent lamp. That is, the halogen lamp HL is a continuous illumination lamp that continuously emits light for at least 1 second or more. In addition, since the halogen lamp HL is a rod-shaped lamp, it has a long life, and by arranging the halogen lamp HL in the horizontal direction, it has excellent radiation efficiency for the semiconductor wafer W above.

Also, in the housing 41 of the halogen lamp box 4, a reflector 43 is provided below the two-stage halogen lamp HL (FIG. 3 ). The reflector 43 reflects the light emitted from the plurality of halogen lamps HL toward the side of the heat treatment space 65.

FIG. 10 is a diagram showing the configuration of the reflectance measuring section 232 provided in the alignment section 230. The reflectance measuring unit 232 includes a light projecting unit 300, a light receiving unit 235, a half mirror 236, and a reflectance estimating unit 31. In the alignment chamber 231 of the alignment part 230, a rotation support part 237 that supports and rotates the semiconductor wafer W, and a rotation motor 238 that rotationally drives the rotation support part 237 are provided. The rotation motor 238 rotates the rotation support portion 237 supporting the semiconductor wafer W, thereby adjusting the orientation of the semiconductor wafer W.

The light projection unit 300 includes a light source such as a halogen light source or an LED light source, and emits light for measuring reflectance. The light receiving unit 235 includes a light receiving element that converts the intensity of the received light into an electrical signal. The light emitted from the light projecting section 300 is reflected by the half mirror 236 and is irradiated vertically to the upper surface of the semiconductor wafer W supported by the rotation support section 237. In the first embodiment, the light emitted from the light projecting section 300 is irradiated to a portion other than the center of rotation of the semiconductor wafer W rotated by the rotation support section 237. The light irradiated from the light projection unit 300 is reflected by the upper surface of the semiconductor wafer W. The reflected light passes through the half mirror 236 and is received by the light receiving unit 235. The reflectance estimating unit 31 estimates the reflectance of the semiconductor wafer W from the intensity of light irradiated by the light projecting unit 300 and the intensity of reflected light received by the light receiving unit 235.

The control unit 3 controls the above-mentioned various operating mechanisms provided in the heat treatment apparatus 100. The configuration of the hardware as the control unit 3 is the same as that of a general computer. That is, the control unit 3 is provided with a place to perform various calculations The circuit that manages is CPU (Central Processing Unit), the special memory for reading basic program is ROM (Read Only Memory), and the memory that can read and write all kinds of information is RAM. (Random Access Memory, random access memory), and pre-memory control software or data disks. The CPU of the control unit 3 performs processing in the heat treatment apparatus 100 by executing a specific processing program. The reflectance estimation unit 31 is a function processing unit realized by the CPU of the control unit 3 executing a specific processing program. In addition, in FIG. 1, the control unit 3 is shown in the indexer unit 101, but it is not limited thereto, and the control unit 3 may be arranged at any position in the heat treatment apparatus 100.

In addition to the above configuration, the heat treatment section 160 is provided with various cooling structures to prevent the halogen lamp box 4, the flash lamp box 5, and the processing chamber 6 from the heat energy generated from the halogen lamp HL and the flash lamp FL during the heat treatment of the semiconductor wafer W Excessive temperature rise. For example, a water cooling pipe (not shown) is provided on the wall of the processing chamber 6. In addition, the halogen lamp box 4 and the flash lamp box 5 form an air-cooling structure in which air flow is performed to exhaust heat. In addition, air is also supplied between the upper chamber window 63 and the light radiation window 53 to cool the flash box 5 and the upper chamber window 63.

Next, the processing operation of the semiconductor wafer W using the heat treatment apparatus 100 of the present invention will be described. The semiconductor wafer W to be processed is a semiconductor substrate on which pattern formation is completed and impurities (ions) are added by ion implantation. The activation of the impurities is performed by flash irradiation heat treatment (annealing) of the heat treatment device 100. Here, after a rough description of the transfer procedure of the semiconductor wafer W in the heat treatment apparatus 100, the heat treatment of the semiconductor wafer W in the heat treatment unit 160 will be described.

First, a plurality of unprocessed semiconductor wafers W that have been patterned and implanted with impurities are placed on the load port 110 of the indexer section 101 in a state of being accommodated in the carrier C. Then, the transfer robot 120 takes out the unprocessed semiconductor wafer W from the carrier C piece by piece, and carries it into the alignment chamber 231 of the alignment part 230. In the alignment chamber 231, the semiconductor wafer W supported by the rotation support portion 237 is rotated about the vertical direction axis in the horizontal plane with the center portion as the rotation center, and the groove is optically detected to adjust the semiconductor wafer W Towards.

In addition, the orientation of the semiconductor wafer W is adjusted, and the reflectance of the surface of the semiconductor wafer W is measured by the reflectance measuring unit 232. The surface of the semiconductor wafer W is a surface on which the main surface of the semiconductor wafer W is patterned and impurities are implanted. The light emitted from the light projecting section 300 of the reflectance measuring section 232 is reflected by the half mirror 236 and irradiated onto the surface of the semiconductor wafer W at an incident angle of 0°. In addition, the light for measuring reflectance emitted from the light projection unit 300 is irradiated onto the surface of the semiconductor wafer W supported and rotated by the rotation support unit 237. Furthermore, the light emitted from the light projecting section 300 is irradiated to a portion of the surface of the semiconductor wafer W other than the rotation center. The light irradiated from the light projection unit 300 is reflected by the surface of the semiconductor wafer W, and the reflected light passes through the half mirror 236 and is received by the light receiving unit 235. The reflectance estimating unit 31 estimates the reflectance of the surface of the semiconductor wafer W by dividing the intensity of the reflected light from the semiconductor wafer W received by the light receiving unit 235 by the intensity of the light irradiated by the light projecting unit 300.

FIG. 11 is a diagram schematically showing a reflectance measurement area in the first embodiment. In the first embodiment, the portion of the surface of the rotating semiconductor wafer W other than the center of rotation is irradiated with light emitted from the light projecting section 300, so the reflectance measurement light is irradiated to the circle of the surface of the semiconductor wafer W环的区301. Therefore, even if various patterns are formed on the surface of the semiconductor wafer W, but Since the circular region 301 including a plurality of parts on the surface of the semiconductor wafer W is irradiated with reflectance measurement light to measure the reflectivity of the circular region 301, it is possible to accurately measure the pattern dependency The reflectivity of the semiconductor wafer W.

Next, the transfer robot 120 of the indexer section 101 takes out the semiconductor wafer W after the adjustment from the alignment chamber 231 and transfers it to the first refrigerating chamber 131 of the cooling section 130 or the second refrigerating chamber 141 of the cooling section 140. The unprocessed semiconductor wafer W carried into the first refrigerating room 131 or the second refrigerating room 141 is carried out to the carrying chamber 170 by the carrying robot 150. When the unprocessed semiconductor wafer W is transferred from the indexer section 101 to the transfer chamber 170 through the first refrigerator compartment 131 or the second refrigerator compartment 141, the first refrigerator compartment 131 and the second refrigerator compartment 141 are used to perform semiconductor wafer W The function of the handover.

The transfer robot 150 from which the semiconductor wafer W has been taken out rotates toward the heat treatment unit 160. Then, the gate valve 185 opens the processing chamber 6 and the transfer chamber 170, and the transfer robot 150 transfers the unprocessed semiconductor wafer W into the processing chamber 6. At this time, when the previously heat-treated semiconductor wafer W exists in the processing chamber 6, one of the transfer robots 151a, 151b takes out the heat-treated semiconductor wafer W, and then removes the unprocessed semiconductor wafer W The wafer W is carried into the processing chamber 6 and the wafer is replaced. Thereafter, the gate valve 185 closes between the processing chamber 6 and the transfer chamber 170.

The semiconductor wafer W carried into the processing chamber 6 is preheated by the halogen lamp HL, and then subjected to flash heat treatment by flash irradiation from the flash lamp FL. The flash heat treatment is used to activate impurities.

After the flash heating process is completed, the gate valve 185 opens the processing chamber 6 and the transfer chamber 170 again, and the transfer robot 150 transfers the semiconductor wafer W after the flash heating process from the process chamber 6 to the transfer chamber 170. The transfer robot 150 from which the semiconductor wafer W has been taken out is rotated from the processing chamber 6 toward the first refrigerator compartment 131 or the second refrigerator compartment 141. In addition, the gate valve 185 closes between the processing chamber 6 and the transfer chamber 170.

Thereafter, the transfer robot 150 transfers the heat-treated semiconductor wafer W into the first refrigerator compartment 131 of the cooling unit 130 or the second refrigerator compartment 141 of the cooling unit 140. In the first refrigerating room 131 or the second refrigerating room 141, the semiconductor wafer W after the flash heating process is cooled. The temperature of the entire semiconductor wafer W at the time when it is carried out from the processing chamber 6 of the heat treatment unit 160 is relatively high, so it is cooled to near normal temperature in the first refrigerator compartment 131 or the second refrigerator compartment 141. After a specific cooling processing time, the delivery robot 120 removes the cooled semiconductor wafer W from the first refrigerator compartment 131 or the second refrigerator compartment 141 and returns it to the carrier C. If a specific number of processed semiconductor wafers W are accommodated on the carrier C, the carrier C is carried out from the load port 110 of the indexer section 101.

The flash heating process in the heat treatment unit 160 will be continuously described. Before the semiconductor wafer W is carried into the processing chamber 6, the valve 84 for gas supply is opened, and the valves 89 and 192 for exhaust are opened to start the supply and exhaust of gas into the processing chamber 6. When the valve 84 is opened, nitrogen gas is supplied from the gas supply hole 81 to the heat treatment space 65. When the valve 89 is opened, the gas in the processing chamber 6 is exhausted from the gas exhaust hole 86. Thereby, the nitrogen gas supplied from the upper part of the heat treatment space 65 in the processing chamber 6 flows downward, and is exhausted from the lower part of the heat treatment space 65.

In addition, by opening the valve 192, the gas in the processing chamber 6 is also exhausted from the transfer opening 66. Furthermore, the atmosphere in the vicinity of the driving section of the transfer mechanism 10 is also exhausted by an exhaust mechanism that is not shown. Furthermore, during the heat treatment of the semiconductor wafer W in the heat treatment section 160, nitrogen gas is continuously supplied to the heat treatment space 65, and the supply amount thereof is appropriately changed according to the processing procedure.

Next, the gate valve 185 is opened to open the transfer opening 66, and the semiconductor wafer W to be processed is transferred into the heat treatment space 65 in the processing chamber 6 through the transfer opening 66 by the transfer robot 150. The transfer robot 150 advances the transfer robot 151a (or transfer robot 151b) holding the unprocessed semiconductor wafer W to a position directly above the holding section 7 and stops. Then, one of the transfer mechanisms 10 moves the transfer arm 11 horizontally from the retreat position to the transfer action position and rises, whereby the jacking pin 12 protrudes from the upper surface of the holding plate 75 of the crystal seat 74 through the through hole 79 to receive Semiconductor wafer W. At this time, the jacking pin 12 rises above the upper end of the substrate support pin 77.

After placing the unprocessed semiconductor wafer W on the ejector pin 12, the transfer robot 150 causes the transfer robot 151a to exit the heat treatment space 65, and the transfer opening 66 is closed by the gate valve 185. Subsequently, the semiconductor wafer W is transferred from the transfer mechanism 10 to the pedestal 74 of the holding portion 7 by being lowered by the pair of transfer arms 11 and held in a horizontal posture from below. The semiconductor wafer W is supported by a plurality of substrate support pins 77 erected on the holding plate 75 and held on the pedestal 74. In addition, the semiconductor wafer W holds the surface on which the pattern is formed and impurities are injected as the upper surface in the holding portion 7. A specific gap is formed between the back surface of the semiconductor wafer W (the main surface on the opposite side to the front surface) supported by the plurality of substrate support pins 77 and the holding surface 75a of the holding plate 75. The pair of transfer arms 11 descending to the lower side of the crystal base 74 are retracted to the retracted position, that is, the recess 62 by the horizontal movement mechanism 13 Inside.

After the semiconductor wafer W is held by the pedestal 74 of the holding portion 7 from below in a horizontal posture, the 40 halogen lamps HL are simultaneously lit to start preheating (auxiliary heating). The halogen light emitted from the halogen lamp HL is irradiated from the lower surface of the semiconductor wafer W through the lower chamber window 64 and the crystal seat 74 formed of quartz. By receiving the light from the halogen lamp HL, the semiconductor wafer W is preheated and the temperature rises. Furthermore, since the transfer arm 11 of the transfer mechanism 10 is retracted to the inside of the recess 62, the heating of the halogen lamp HL is not hindered.

When the halogen lamp HL is used for preheating, the temperature of the semiconductor wafer W is measured by the radiation thermometer 20. That is, the infrared temperature radiated from the lower surface of the semiconductor wafer W held on the pedestal 74 through the opening 78 is received by the radiation thermometer 20 to measure the temperature of the wafer during the temperature increase. The measured temperature of the semiconductor wafer W is transferred to the control unit 3. The control unit 3 controls the output of the halogen lamp HL while monitoring whether the temperature of the semiconductor wafer W heated up by the light irradiation from the halogen lamp HL has reached a specific preheating temperature T1. That is, the control unit 3 performs feedback control on the output of the halogen lamp HL so that the temperature of the semiconductor wafer W becomes the preheating temperature T1 based on the measurement value of the radiation thermometer 20. The preheating temperature T1 is set to about 600° C. to 800° C., and there is no possibility that impurities added to the semiconductor wafer W will diffuse due to heat in this temperature range (700° C. in this embodiment).

After the temperature of the semiconductor wafer W reaches the preheating temperature T1, the control unit 3 temporarily maintains the semiconductor wafer W at the preheating temperature T1. Specifically, when the temperature of the semiconductor wafer W measured by the radiation thermometer 20 reaches the preheating temperature T1, the control unit 3 adjusts the halogen lamp HL The output of the semiconductor wafer W is maintained at approximately the preheating temperature T1.

By performing such preheating using the halogen lamp HL, the entire semiconductor wafer W is uniformly heated to the preheating temperature T1. At the stage of pre-heating using the halogen lamp HL, the temperature of the peripheral portion of the semiconductor wafer W that is more likely to generate heat tends to be lower than that of the central portion, but the arrangement density of the halogen lamp HL of the halogen lamp box 4 is The area facing the central portion of the semiconductor wafer W is higher than the area facing the peripheral portion. Therefore, the amount of light irradiated to the peripheral portion of the semiconductor wafer W that easily generates heat is increased, and the in-plane temperature distribution of the semiconductor wafer W in the preheating stage can be made uniform.

When the temperature of the semiconductor wafer W reaches the preheating temperature T1 and a specific time passes, the flash lamp FL flashes the surface of the semiconductor wafer W. At this time, part of the flash light radiated from the flash lamp FL directly faces the processing chamber 6, and the other part is temporarily reflected by the reflector 52 and then faces the processing chamber 6, and the flash heating of the semiconductor wafer W is performed by the irradiation of these flash lights .

Flash heating is performed by flashing light from the flash lamp FL, so that the surface temperature of the semiconductor wafer W can be raised in a short time. That is, the flash light irradiated from the flash lamp FL is an extremely short and strong flash light that converts the electrostatic energy previously stored in the capacitor into a very short light pulse and has an irradiation time of about 0.1 milliseconds or more and 100 milliseconds or less. Furthermore, the surface temperature of the semiconductor wafer W heated by flash by the flash irradiation from the flash lamp FL instantaneously rises to the processing temperature T2 of 1000° C. or more, and after the impurities injected into the semiconductor wafer W are activated, the surface temperature drops rapidly. In this way, the surface temperature of the semiconductor wafer W can be raised in a very short time Therefore, it is possible to activate the impurities while suppressing the diffusion of the impurities injected into the semiconductor wafer W due to heat. In addition, the time required for the activation of impurities is extremely short compared to the time required for thermal diffusion, so even if it is about 0.1 milliseconds to 100 milliseconds without a short time without diffusion, the activation can be completed.

In addition, at the time of flash irradiation, the luminous intensity of the flash lamp FL is corrected based on the reflectance of the surface of the semiconductor wafer W estimated by the reflectance estimation unit 31. When the flash lamp FL irradiates a silicon semiconductor wafer (bare wafer) of which neither patterning nor impurity implantation is completed, the temperature reached on the surface of the bare wafer is investigated in advance and is known. Also, the reflectance of the surface of the bare wafer is also known. Further, according to the ratio of the surface reflectance of the bare wafer to the surface reflectance of the semiconductor wafer W estimated by the reflectance estimation section 31, the flash lamp FL to the capacitor is adjusted so that the surface temperature of the semiconductor wafer W reaches the processing temperature T2 Charging voltage. As a result, when the semiconductor wafer W to which the pattern or film is to be processed is irradiated with flash, the surface of the semiconductor wafer W can be accurately heated to the processing temperature T2.

After the flash heating process ends, the halogen lamp HL goes out after a certain period of time. As a result, the semiconductor wafer W is rapidly cooled from the preheating temperature T1. The temperature of the semiconductor wafer W during the cooling is measured by the radiation thermometer 20, and the measurement result is transmitted to the control unit 3. The control unit 3 monitors whether the temperature of the semiconductor wafer W has decreased to a specific temperature based on the measurement result of the radiation thermometer 20. Then, after the temperature of the semiconductor wafer W has fallen below a certain temperature, one of the transfer mechanisms 10 moves the pair of transfer arms 11 horizontally from the retreat position to the transfer operation position again, thereby lifting the pin 12 from the crystal The upper surface of the pedestal 74 protrudes and receives the heat-treated semiconductor wafer W from the pedestal 74. Then, the closed transport opening 66 is opened by the gate valve 185, and the processed semiconductor wafer W placed on the jacking pin 12 is transported by the transport robot 151b (or transporter) of the transport robot 150 Manipulator 151a) moves out. The transfer robot 150 causes the transfer robot 151b to enter the position immediately below the semiconductor wafer W ejected by the ejector pin 12, and then stops. Then, the pair of transfer arms 11 is lowered, and the flash-heated semiconductor wafer W is delivered and placed on the transfer robot 151b. Thereafter, the transport robot 150 causes the transport robot 151b to exit the processing chamber 6 and transport out the processed semiconductor wafer W.

In the first embodiment, the surface of the rotating semiconductor wafer W is irradiated with light for measuring reflectance to measure the reflectance of the annular region 301 on the surface. Therefore, even if various patterns are formed on the surface of the semiconductor wafer W, since the reflectance of the ring-shaped region 301 including a plurality of locations on the surface is measured, the semiconductor wafer can be accurately measured while suppressing the pattern dependency W reflectivity. As a result, the light emission intensity of the flash lamp FL can be accurately adjusted according to the reflectance of the semiconductor wafer W measured by suppressing the pattern dependency.

<Second Embodiment>

Next, the second embodiment of the present invention will be described. The overall configuration of the heat treatment apparatus 100 of the second embodiment is almost the same as that of the first embodiment. In addition, the processing sequence of the semiconductor wafer W in the heat treatment apparatus 100 of the second embodiment is also substantially the same as that of the first embodiment. When measuring the reflectance, the semiconductor wafer W is rotated in the first embodiment to measure the reflectance of the annular region 301. In the second embodiment, a plurality of light-receiving portions are provided to measure the complex number of the semiconductor wafer W The reflectivity of each part.

FIG. 12 is a diagram showing the configuration of the reflectance measuring unit 232 of the second embodiment. In FIG. 12, the same elements as those in the first embodiment are given the same symbols. Reflection of the second embodiment The rate measuring section 232 includes three light receiving sections 235a, 235b, and 235c at different installation positions. The light for measuring reflectance emitted from the light projection unit 300 is reflected by the half mirror 236 and irradiated onto the surface of the semiconductor wafer W supported by the rotation support unit 237. In the second embodiment, light irradiated from one light projection unit 300 and reflected unidirectionally on the surface of the semiconductor wafer W is received by three light receiving units 235a, 235b, and 235c. Therefore, the reflected positions of the reflected light received by the three light receiving portions 235a, 235b, and 235c on the wafer surface are different from each other. That is, the three light-receiving portions 235a, 235b, and 235c receive the reflected light reflected by the reflectance measurement light irradiated from one light-projecting portion 300 through three different portions on the surface of the semiconductor wafer W. The reflectance estimating unit 31 estimates the reflectance of each of the reflection positions of the three parts from the intensity of the light irradiated by the light projecting unit 300 and the intensity of the reflected light received by each of the three light receiving units 235a, 235b, and 235c. Then, the reflectance estimation unit 31 estimates the average reflectance, which is the average of the reflectances of the three parts on the wafer surface, as the reflectance of the semiconductor wafer W.

Except for the reflectance measurement, the rest of the second embodiment is the same as the first embodiment. In the second embodiment, the reflectance of the plurality of parts is estimated from the intensity of the reflected light reflected from the plurality of parts on the surface of the semiconductor wafer W, and the average value thereof is estimated as the reflectance of the semiconductor wafer W. Therefore, even if various patterns are formed on the surface of the semiconductor wafer W, the reflectance of the semiconductor wafer W can be accurately measured by suppressing the pattern dependency due to measuring the reflectance of a plurality of parts on the surface.

<Third Embodiment>

Next, a third embodiment of the present invention will be described. The overall configuration of the heat treatment apparatus 100 of the third embodiment is almost the same as that of the first embodiment. In addition, the processing sequence of the semiconductor wafer W in the heat treatment apparatus 100 of the third embodiment is also substantially the same as that of the first embodiment. On the 1st In the second embodiment, the reflectance of a plurality of parts of the semiconductor wafer W is measured, but in the third embodiment, the scattering component of a specific part of the semiconductor wafer W is measured.

FIG. 13 is a diagram showing the configuration of the reflectance measuring unit 232 of the third embodiment. In FIG. 13, the same elements as those in the first and second embodiments are denoted by the same symbols. The configuration of the reflectance measuring unit 232 of the third embodiment is similar to that of the second embodiment, and includes three light receiving units 235a, 235b, and 235c at different installation positions. The light for measuring reflectance emitted from the light projection unit 300 is reflected by the half mirror 236 and irradiated onto the surface of the semiconductor wafer W supported by the rotation support unit 237. In the third embodiment, the three light receiving portions 235a, 235b, and 235c receive light irradiated from one light projecting portion 300 and reflected by a specific portion on the surface of the semiconductor wafer W. In other words, the reflected positions of the wafer surface of the reflected light received by the three light receiving portions 235a, 235b, and 235c are common. In the third embodiment, as shown in FIG. 13, from a macro viewpoint, the light for measuring the reflectance irradiated from the light projecting section 300 is not reflected unidirectionally on the surface of the semiconductor wafer W but scattered at the above-mentioned specific site . This phenomenon occurs, for example, when a three-dimensional pattern is formed on the surface of the semiconductor wafer W. Furthermore, the scattering phenomenon may occur at all parts where the three-dimensional pattern is formed, so the specific part of the so-called semiconductor wafer W does not refer to a fixed part on the wafer surface, but an arbitrary part.

In the third embodiment, the three light receiving portions 235a, 235b, and 235c receive the reflectance measurement light irradiated from the one light projecting portion 300, and the reflected light is reflected by a specific portion of the surface of the semiconductor wafer W at different angles Light. The reflectance estimation unit 31 measures the intensity of the light irradiated from the light projecting unit 300 and the intensity of the reflected light received by each of the three light-receiving units 235a, 235b, and 235c in addition to measuring the reflectance of the specific site ingredient.

The third embodiment is the same as the first embodiment except for the reflectance measurement. In the third embodiment, the intensity of a plurality of reflected lights after being reflected at different angles from a specific part of the surface of the semiconductor wafer W is measured in addition to the reflectance of the specific part, and the scattering component is also measured. Therefore, even if a three-dimensional pattern is formed on the surface of the semiconductor wafer W, since the scattering component at a specific part of the surface is also measured, the reflectivity of the semiconductor wafer W can be accurately measured while suppressing the pattern dependency.

<variation example>

The embodiments of the present invention have been described above, but the present invention can be variously modified other than the above-mentioned cases as long as the present invention does not deviate from the gist. For example, in the first embodiment, it is also possible to provide a plurality of light projecting portions 300 that irradiate reflectance measurement light to a plurality of locations with different distances from the center of rotation of the semiconductor wafer W, and a plurality of the measurement diameters are different The reflectivity of the circular area. As long as the average value of the reflectance of a plurality of annular regions with different equal diameters is estimated, the reflectance of the semiconductor wafer W can be accurately measured by further suppressing the pattern dependency.

In the first embodiment, the reflectivity of the circular region 301 was measured, but it is not limited to this, and the reflection of the circular arc region may be measured without the rotation angle of the semiconductor wafer W reaching 360°. rate. Even in this way, since the reflectance of the arc-shaped region including a plurality of parts on the surface of the semiconductor wafer W is measured, the reflectivity of the semiconductor wafer W can be accurately measured while suppressing the pattern dependency.

Furthermore, in the first embodiment, the semiconductor wafer W is rotated relative to the fixed light projecting portion 300 However, in contrast to this, the reflectance measurement light may be used to scan the semiconductor wafer W in a stationary state or in rotation. Furthermore, the semiconductor wafer W may be moved linearly with respect to the light projection unit 300, for example. That is, the semiconductor wafer W may be relatively moved with respect to the light for measuring reflectance emitted from the light projection unit 300.

Furthermore, in the second embodiment, the average value of the reflectances of the plural portions of the semiconductor wafer W is estimated, but it is not necessary to estimate the average value. When the average value is not obtained, the intensity of the light irradiated from the flash lamp FL to each of the plurality of parts may be adjusted according to the measured reflectance of the plurality of parts. For example, it is only necessary to adjust the intensity of light irradiated to the peripheral portion of the semiconductor wafer W from the flash lamps FL arranged at the ends in the arrangement of the plurality of flash lamps FL according to the reflectance of the peripheral portion of the semiconductor wafer W. Thereby, according to the measured reflectivity of the semiconductor wafer W, the luminous intensity of the flash lamp FL can be adjusted in such a way that the in-plane temperature distribution of the semiconductor wafer W is more uniform.

In addition, in the second embodiment, the average reflectance of the three parts may be estimated from the intensity of the combined reflected light obtained by combining the reflected light received by the three light receiving parts 235a, 235b, and 235c with the optical fiber.

In addition, in the second and third embodiments, the number of light-receiving parts is not limited to three, as long as it is two or more.

In addition, in the above embodiment, the flash box 5 is provided with 30 flashes FL, but it is not limited to this, and the number of flashes FL may be any number. Also, the flash FL is not limited to xenon The flash can also be a krypton flash. In addition, the number of halogen lamps HL provided in the halogen lamp box 4 is not limited to 40, and may be any number.

In addition, in the above embodiment, the halogen lamp HL of the filament system is used as a continuous illuminating lamp that continuously emits light for 1 second or longer to perform preheating of the semiconductor wafer W, but it is not limited to this, and may be used instead of the halogen lamp HL Discharge type arc lamps (such as xenon arc lamps) are used as continuous lighting lamps for preheating. Alternatively, the wafer holder holding the semiconductor wafer W may be placed on a heating plate, and the semiconductor wafer W may be preheated by heat conduction from the heating plate.

In addition, according to the heat treatment apparatus 100, the substrate to be processed is not limited to a semiconductor wafer, and may be a glass substrate used for a flat panel display such as a liquid crystal display device or a substrate for a solar cell. In addition, the technology of the present invention can also be applied to heat treatment of a high dielectric constant gate insulating film (High-k film), bonding of metal to silicon, or crystallization of polycrystalline silicon.

3: Control Department

31: Reflectance estimation department

232: Reflectance measurement section

235a: Light receiving department

235b: Light receiving department

235c: Light receiving department

236: Half mirror

237: Rotating support

238: Rotating motor

300: Projection Department

Claims (6)

A heat treatment method, characterized in that it heats the substrate by irradiating the substrate with light, and includes: a heating step of irradiating the substrate with light from a heating lamp to heat the substrate; the irradiation step of the substrate The portion of the rotating substrate other than the center of rotation is irradiated with light for measuring reflectance; the light receiving step, which receives the reflected light reflected by the substrate from the light irradiated in the irradiation step; and the step of estimating the reflectance, which is derived from the above The intensity of the light irradiated in the irradiation step and the intensity of the reflected light received in the light receiving step are used to calculate the reflectance of the substrate. The heat treatment method according to claim 1, wherein in the irradiation step, a plurality of portions of the substrate having different distances from the rotation center are irradiated with light for measuring reflectance. A heat treatment method, characterized in that it heats the substrate by irradiating the substrate with light, and includes: a heating step of irradiating the substrate with light from a heating lamp to heat the substrate; the irradiation step of the substrate The substrate is irradiated with light for measuring reflectance; a light-receiving step is a method in which the light irradiated by the light-receiving parts is reflected by a plurality of parts of the substrate through the light-receiving part; and a reflectance estimation step is obtained from the above The intensity of the light irradiated in the irradiation step is the same as the above In the light-receiving step, the intensity of the reflected light received by the plurality of light-receiving parts estimates the reflectance of the plurality of parts of the substrate. The heat treatment method according to claim 3, wherein in the above-mentioned reflectance estimation step, the average reflectance of the average of the reflectances of the plurality of locations is estimated. The heat treatment method according to claim 3, wherein the intensity of light irradiated from the heating lamp to the plurality of parts in the heating step is adjusted according to the reflectances of the plurality of parts estimated in the reflectance estimation step. A heat treatment method, characterized in that it heats the substrate by irradiating the substrate with light, and includes: a heating step of irradiating the substrate with light from a heating lamp to heat the substrate; the irradiation step of the substrate The substrate is irradiated with light for measuring reflectance; the light receiving step is a method in which the light irradiated in the irradiation step is received by a plurality of light-receiving parts to reflect the reflected light from a specific part of the substrate; and the reflectivity estimation step is derived from the above The intensity of the light irradiated in the irradiation step and the intensity of the reflected light received by the plurality of light-receiving portions in the light-receiving step are used to estimate the reflectance of the specific portion of the substrate.

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