KR20020028824A - Light illuminating type heating processing apparatus and method therefor - Google Patents

Abstract

The present invention is intended to enable uniform heating of the wafer and to efficiently heat the guard ring.

The lamps L1 to L10 of the light source unit 1 are composed of wafer heating lamps L1 to L8 and guard ring heating lamps L9 and L10. Then, the distance from the guard ring heating lamps L9 and L10 to the guard ring 3 is made larger than the distance from the wafer heating lamps L1 to L8 to the wafer W and the lamps L1 to L8. With the side walls 4 between the lamps L9 and L10 as mirror surfaces, the light irradiated from the lamps L9 and L10 and directed toward the wafer W is reflected in the guard ring 3 direction. Moreover, the 2nd side wall 5 is formed in the outer periphery of guard ring heating lamp L9, L10, and this side wall 5 is used as a reflecting surface. Moreover, the 2nd mirror 6 is provided in the outer periphery of the guard ring 3, and the light irradiated to the outer side of the guard ring 3 is condensed on the guard ring 3.

Description

Light illuminating type heating processing apparatus and method therefor}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light irradiation type heat treatment apparatus and a light irradiation type heat treatment method for rapidly heating, maintaining a high temperature, and rapidly cooling a semiconductor wafer (hereinafter referred to as a wafer) for film formation, diffusion, and annealing.

The light irradiation type heat treatment in the semiconductor manufacturing process is performed over a wide range such as film formation, diffusion, and annealing. Any treatment is to heat the wafer to a high temperature.

When the light irradiation type heat treatment apparatus is used for this heat treatment, the wafer can be rapidly heated, and the temperature can be raised from several seconds to several tens of seconds to 1000 ° or more. And if light irradiation is stopped, it can cool rapidly.

However, if the temperature distribution is uneven in the wafer when the wafer is heated, a phenomenon called slip, that is, a defect in crystal potential, may occur in the wafer, resulting in a defective product. Therefore, when heat-processing a wafer using a light irradiation type heat treatment apparatus, it is necessary to heat, maintain high temperature, and cool so that the temperature distribution of a wafer may become uniform.

For example, when the wafer is heated to 1050 ° C., if a temperature difference of 2 ° C. or more occurs within the wafer surface, there is a possibility that the slip occurs. In order to suppress the occurrence of slip, it is preferable to keep the temperature difference in the wafer surface within 1 ° C.

In addition, when the wafer is heated for film formation, in order to form a film with a uniform thickness, the wafer must be heated with high precision in-plane uniformity.

In the light irradiation type heat treatment apparatus, even when the wafer is kept at a high temperature, even if the entire surface of the wafer is irradiated with uniform irradiance, the temperature of the peripheral portion of the wafer decreases. For example, the oxidation of the wafer is generally performed by heating the wafer to about 1100 ° C., but when the temperature at the center of the wafer is 1100 ° C., the temperature of the periphery is about 30 ° C. lower than the central part, causing the slip. .

The temperature around the wafer is lowered because heat is radiated from the side of the wafer. Thermal radiation from the wafer side causes heat flow in the wafer, resulting in a temperature distribution. As a method of preventing this, the method of arrange | positioning the auxiliary material of heat capacity equivalent to a wafer so that the outer periphery of a wafer is proposed previously is proposed. Such auxiliary materials are generally called guard rings.

If the wafer and the guard ring are seen as a single plate-like body integrated with each other, when the wafer and the guard ring are both heated by uniform light irradiation, since the periphery of the wafer does not become the periphery of the plate-shaped body, the temperature of the wafer periphery Does not degrade.

In addition, since the guard ring is provided so as to surround the outer circumference of the wafer, a mechanism for retaining the circumference of the wafer can be added thereto, and the guard ring can also serve as a wafer holding material. Therefore, in many cases, the guard ring has a function of holding a wafer.

In other words, the guard ring is a member that compensates for the temperature drop caused by the radiation of heat on or near the side of the wafer and makes the temperature of the wafer uniform, and is often used as a wafer holding material.

In practice, however, it is difficult to fabricate the guard ring so as to be integral with the wafer (that is, to make the heat capacity equal). The reason is as follows.

(1) It is very difficult to produce the guard ring from the same material as the wafer.

When the guard ring is made of silicon (Si), which is the same material as the wafer, the heat capacity of the wafer and the guard ring can be made equal. However, silicon is very difficult to process into a shape holding a wafer, and when repeatedly exposed to a large temperature difference, the silicon is deformed, and it cannot function as a guard ring.

(2) It is relatively easy to process, and its heat capacity is somewhat larger than that of silicon, but silicon carbide (SiC) is used as a material having a close value, and this silicon carbide is generally used as the guard ring.

However, since silicon carbide cannot be made thinner than 1 mm due to processing problems (yield), it becomes thicker than the thickness of wafers from 0,7 to 0.8 mm.

(3) The heat capacity of the guard ring is about 1.5 times larger per unit area than the wafer when heated at a high temperature due to the difference in specific heat between silicon and silicon carbide and the difference in thickness. Therefore, in order to eliminate the said heat capacity difference between a wafer and a guard ring, it is necessary to heat a guard ring with power larger than a wafer.

11 shows an example of the configuration of a conventional light irradiation type heat treatment apparatus. The figure shows the cross-sectional structure which cut | disconnected the light irradiation type heat processing apparatus to the surface orthogonal to the wafer surface through the center.

As shown in FIG. 11, in the light source part 1, circular-shaped filament lamps L2 to L10 having different diameters of a plurality of circles (9 in this example) are arranged concentrically at equal intervals (20 mm). It is. The diameter of the ring of the lamp L2 disposed at the innermost side is 50 mm, and a lamp L1 having a shape sealed at one end is attached to the inner side of the lamp L2. The input power of the annular lamps L2 to L10 is 240 W / cm, for example.

Behind the lamps L2 to L10, a corrugated mirror 1a for reflecting light from the lamps L2 to L10 to the wafer W side is provided. Light from the light source unit 1 is reflected directly from the lamps L1 to L10 or reflected on the mirror 1a and placed on the guard ring 3 through the quartz window 2 (thickness 20 mm in this example). The wafer W is irradiated. The distance from the lamps L1 to L10 to the wafer W is 50 mm in this example.

The guard ring 3 is held by the holding material 12 provided in the chamber 11, and the guard ring 3 also serves as a wafer holding material.

As shown in FIG. 11, the light source unit 1 is provided with lamps L1 to L8 for irradiating the region where the wafer W exists, as well as lamps L9 and L10 for widening the light irradiation region. The guard ring 3 was also heated by light irradiation.

As described above, the guard ring 3 is produced by processing silicon carbide, and as described above, the heat capacity is about 1.5 times larger than that of the wafer. For this reason, the input of the lamps L9 and L10 is increased to increase the output power, and the light ring is irradiated by the guard ring 3 so as to solve the heat capacity difference.

However, since light from lamps L9 and L10 for widening the light irradiation area is spread and irradiated, not only the guard ring 3 but also the wafer W is irradiated. Therefore, when the output from the lamps L9 and L10 is increased and irradiated, the temperature of the wafer W also rises, making it difficult to heat at a uniform temperature.

In addition, even if the output from the lamps L9 and L10 is increased, the irradiated light is spread, so that light energy sufficient to solve the difference in heat capacity between the wafer W and the guard ring 3 can be efficiently applied to the guard ring. It is difficult. For this reason, the temperature of the guard ring is discontinuously decreased at the portion where the wafer W and the guard ring 3 are in contact with each other, which causes slippage.

In other words, when the output from the lamps L9 and L10 is increased, the irradiance is also increased in the portion of the guard ring 3, but is also irradiated to the wafer W, so that the irradiance around the wafer is also increased. For this reason, the temperature of the wafer W becomes high as it goes to the peripheral part. On the other hand, since light from the lamps L9 and L10 is spread, energy cannot be obtained in the guard ring 3 as much as to compensate for the heat capacity difference. Therefore, the temperature discontinuously decreases at the portion where the wafer W and the guard ring 3 contact each other, and slip occurs at the peripheral portion where the temperature is uneven.

Further, in order to provide energy for compensating for the difference in heat capacity between the wafer W and the guard ring 3, the input to the lamps L9 and L10 must be made larger, so that the efficiency is deteriorated.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to condense light from a lamp for heating the guard ring only to the guard ring, thereby enabling uniform heating of the wafer and efficiently heating the guard ring. It is doing well.

1 is a view showing a cross-sectional structure of the light irradiation type heat treatment apparatus of the embodiment of the present invention,

2 shows a holding portion of a wafer by a guard ring;

3 is a view showing a configuration example in the case where the guard ring is arranged around the wafer to hold the wafer with the holding material;

4 is a diagram showing the size and distribution of irradiance irradiated on the wafer and guard ring surfaces in the structure of FIG. 1 (when θ = 20 °);

FIG. 5 is a view showing the illumination intensity from the lamps L1 to L10 under the conditions of FIG. 4;

6 is a diagram showing the size and distribution of irradiance irradiated on the wafer and guard ring surfaces in the structure of FIG. 1 (when θ = 15 °),

7 is a diagram showing an example of the configuration when a second mirror is provided around the guard ring;

8 is a view showing a configuration example in the case where an inclined surface is provided in the chamber instead of the second mirror;

9 is a diagram showing the size and distribution of irradiance irradiated on the wafer and guard ring surfaces when the second mirror is installed in the structure of FIG. 1 (when θ = 20 °);

10 is a conceptual diagram showing the distribution of irradiance and temperature irradiated to the wafer and the guard ring in the prior art and the present application;

11 is a view showing an example of the configuration of a conventional light irradiation type heat treatment apparatus;

<Explanation of symbols for the main parts of the drawings>

1: light source 1a: mirror

2: quartz window 3: guard ring

4: first sidewall 5: second sidewall

6: second mirror 11: chamber

12, 13, 14: holding material L1-L10: lamp

W: Wafer

In this invention, the said subject is solved by the following method.

(1) A plurality of filament lamps having a circular ring shape and different diameters of the circular ring are arranged concentrically, and provided with a light source portion provided with a mirror on the rear surface of the filament lamp, and a wafer disposed on the opposite side of the mirror, In a light irradiation type heat treatment apparatus provided with a guard ring at the periphery of the wafer, the plurality of filament lamps of the light source unit are provided on the outer periphery of the first lamp group and the first lamp group provided to face the wafer. It consists of a 2nd lamp group provided opposed to a ring, and it prevents the light emitted from the said 2nd lamp group from irradiating a wafer.

That is, the distance of the light irradiation direction (direction perpendicular to the wafer surface) from the lamp of the second lamp group to the guard ring is the distance of the light irradiation direction (direction perpendicular to the wafer surface) from the lamp of the first lamp group to the wafer. It is made larger and the side wall formed between the 2nd lamp group and the 1st lamp group is made into the mirror surface, and the light which irradiates from the lamp of the 2nd lamp group by this side wall toward the wafer direction is reflected in the guard ring direction. do.

Thereby, the light from the lamp of the 2nd lamp group can be prevented from irradiating a wafer, and the light of that much can be condensed on a guard ring.

(2) In (1), a second side wall is formed on the outermost periphery of the second lamp group in a direction open to the light irradiation direction to reflect the light emitted from the second lamp group in the direction of the guard ring. Form.

That is, the 2nd side wall angled in the opening direction with respect to the direction to which light is irradiated to the outer periphery of a 2nd lamp group is formed, and this side wall is used as a reflective surface.

Thereby, the light irradiated toward the outer side of the guard ring from the lamp of the 2nd lamp group can be condensed on the guard ring, and the energy of the light irradiated to the guard ring can be enlarged.

(3) In (1) and (2), a second mirror is provided on the outer circumference of the guard ring to reflect light emitted from the second lamp group in the direction of the guard ring.

That is, a second mirror is provided on the outer circumference of the guard ring at an angle in the opening direction with respect to the direction of the light source portion. Thereby, the light irradiated to the outer side of a guard ring can be condensed to a guard ring, and the energy of the light irradiated to a guard ring can be enlarged.

(Example)

Fig. 1 shows a cross-sectional structure of the light irradiation type heat treatment apparatus of the embodiment of the present invention.

In the figure, 1 is a light source unit, L1 to L8 are wafer heating lamps, and shapes, arrangement intervals, input power, and the like are the same as in the conventional example shown in FIG.

2 is a quartz window, 3 is a guard ring, and the guard ring 3 is held by the holding material 12 provided in the chamber 11. The wafer W is placed on the guard ring 3, and the guard ring 3 also serves as a wafer holding material.

The holding part of the wafer W of the guard ring 3 is, for example, as shown in FIG. 2, and the edge is cut, and is in linear contact with the guard ring 3 and the edge part of the wafer W. As shown in FIG.

The lamps L9 and L10 are lamps for guard ring heating. The input power of the lamps L9 and L10 is larger at 300 W / cm than the wafer heating lamps L1 to L8. Since the pipe diameter becomes rather thick, the pitch of the arrangement is, for example, 21 mm between the lamps L8-L9 and 22 mm between the lamps L9, L10.

The lamps L9-L10 are arranged at, for example, 30 mm farther than the distance (50 mm) from the lamps L2 to L8 to the wafer.

Since it was set as the above structure, as shown in FIG. 1, the side wall 4 arises between the wafer heating lamp L8 and the guard ring heating lamp L9 (this side wall is called a 1st side wall). By making this side wall 4 a reflecting surface, the light irradiated from the guard ring heating lamps L9 and L10 toward the wafer W is reflected in the guard ring 3 direction.

Accordingly, even if the input of the lamps L9 and L10 is made large, the light is not irradiated to the wafer W. Therefore, the temperature of the wafer does not rise, and uniform heating is enabled by the control of the wafer heating lamp. Moreover, since the light irradiated toward the wafer W direction is reflected in the guard ring 3 direction, the energy of the light irradiated to the guard ring 3 becomes larger than the conventional example. Therefore, the guard ring 3 can be heated efficiently.

Moreover, the 2nd side wall which has a reflecting surface which has the angle (theta) which spreads outward with respect to the direction (right direction with respect to a wafer surface) to which light is irradiated to the outer peripheral part of the outermost lamp L10 in a guard ring heating lamp. (5) is installed. Moreover, angle (theta) is an angle of the reflecting surface of the 2nd side wall 5 with respect to the direction to which light is irradiated.

Light irradiated outward from the lamps L9 and L10 is reflected by the second side wall 5 in the direction of the guard ring 3.

With the above configuration, since the light irradiated toward the outside and not contributing to the heating of the guard ring 3 is reflected in the direction of the guard ring 3, the energy of the light irradiated to the guard ring 3 increases. Therefore, the guard ring 3 can be heated efficiently.

In addition, although the cross-sectional shape of the reflecting surface of the 2nd side wall 5 is linear form in FIG. 1, an ellipse, a parabola, etc. make the said cross-sectional shape so that the light irradiated from the lamps L9 and L10 may be condensed on the guard ring 3. It is good also as a curved shape of.

1 is an example in which the guard ring 3 also serves as a wafer holding material, but a wafer holding material may be separately provided to hold the wafer W. As shown in FIG.

That is, as shown in FIG. 3, the guard ring 3 is arranged near the periphery of the wafer W, and the wafer W and the guard ring 3 are held by the holding materials 13 and 14, respectively. For example, it maintains three points of support. In addition, since the wafer W is bent by its own weight, the holding material 13 is disposed at a position where the amount of warpage of the wafer W is as small as possible.

In Fig. 4, in the structure having the first side wall 4 and the second side wall 5, the size and distribution of the irradiance irradiated on the wafer and guard ring surfaces are shown. The horizontal axis is the horizontal distance (mm) from the center of the wafer, and the vertical axis is the relative value of the irradiance irradiated on the wafer and the guard ring surface, and the range of 0 to 150 mm of the horizontal axis is the area of the wafer W, and the range of 150 to 170 mm is This is the area of the guard ring 3. In addition, the irradiance of the same figure was calculated | required by calculation.

The figure shows the case where the angle [theta] of the second side wall 5 is 20 [deg.]. As shown in FIG. 1, the wafer heating lamps guard eight of the lamps L1 to L8. Two ring heating lamps are used, L9 and L10.

Each curve shown in FIG. 4 shows to which region the light of each lamp L1 to L8 is radiated and irradiated, and one zone of the figure shows the magnitude of the irradiance irradiated by the lamp L1. And distribution, and similarly below, 2-10 zone has shown the magnitude | size and distribution of the irradiance irradiated by lamp | ramp L2-L10.

For example, the light from the six-zone lamp L6 has a peak of irradiance around 105 mm from the center of the wafer W just below the lamp, and is wide from the center of the wafer W to the outside of the guard ring 3. The area is irradiated. The light from any one of the lamps L1 to L8 among the zones 1 to 8 for wafer heating is also irradiated to a wide range.

On the other hand, the light from 9 or 10 zone lamps L9 and L10, which are guard ring heating lamps, has a peak of illuminance in the region outside the guard ring at 160 mm from the center of the wafer W as the guard ring 3. The amount irradiated to the wafer W is small, and in particular, it is not irradiated to the inside of 100 mm from the center of the wafer W.

Therefore, even if the output power of the lamps L9 and L10 in the 9 and 10 zones is increased, the wafer W can be heated to a minimum, and in a state where the in-plane temperature of the wafer W is kept uniform. Only the guard ring 3 can be heated to compensate for the difference in heat capacity between the wafer W and the ring 3.

FIG. 5 shows the illumination illuminance from each of the lamps L1 to L10 under the conditions of FIG. 4. As in FIG. 4, the horizontal axis is a horizontal distance (mm) from the center of the wafer, and the center axis of the figure is the center of the wafer. In addition, the vertical axis is the relative value of the irradiance irradiated on the wafer and the guard ring surface, the range of 0 to ± 150 mm of the horizontal axis is the area of the wafer W, and the range of ± 150 mm to ± 170 mm is the guard ring (3). ) Area.

From the figure, by providing the 1st side wall 4 and the 2nd side wall 5, the substantially uniform light energy is irradiated on the inside of the wafer W surface, and it can irradiate only the guard ring 3 part with big irradiance. It can be seen that there is.

Moreover, when arrangement | positioning of 9 and 10-zone lamps L9 and L10 and the shape of the mirror is the same as FIG. 11 of a prior art example, it is the same as the curve by the lamp of 1-8 zones on the outer side of 8 zone in FIG. By adding two curves, light from the nine and ten zone lamps L9 and L10 is irradiated to the center of the wafer.

In this case, if the guard ring is to be heated, and the input of the lamps L9 and L10 in the 9 and 10 zones is increased, the guard ring is heated to the inner region of the wafer W and the temperature is increased.

FIG. 6 shows the magnitude and distribution of irradiance when the angle θ of the second side wall 5 is 15 °. 4, the horizontal axis is the horizontal distance (mm) from the center of the wafer, the vertical axis is the relative value of the irradiance irradiated to the wafer and the guard ring surface, and the range of 0 to 150 mm of the horizontal axis is the area of the wafer W, The range of 150 mm-170 mm is an area of the guard ring 3.

As can be seen from FIG. 4 and FIG. 6, by changing the angle θ of the second sidewall 5, the guard ring is heated without changing the distribution of irradiation by the wafer heating lamps L1 to L8. The distribution of irradiation by the lamps L9 and L10 can be changed. By setting the said angle (theta) suitably, the quantity irradiated to the wafer W by the light from the guard ring heating lamps L9 and L10 can be made small, and the quantity irradiated to the guard ring 3 can be made large.

The distribution of irradiation by the guard ring heating lamps L9 and L10 by changing not only the angle θ of the second sidewall 5 but also the heights of the first sidewall 4 and the second sidewall 5. Can change.

Moreover, in order to increase the energy of the light irradiated to a guard ring, as shown in FIG. 7, the 2nd mirror 6 which has an angle (alpha) spread with respect to the direction of a light source part is provided in the periphery of a guard ring. Moreover, angle (alpha) is an angle of the reflecting surface of the 2nd mirror 6 with respect to the plane (plane parallel to a wafer surface) perpendicular | vertical to a light irradiation direction, and the 2nd mirror 6 is in the perimeter of a guard ring. Is installed.

Thereby, the light irradiated to the outer side of the guard ring 3 from the guard ring heating lamps L9 and L10 is reflected by the 2nd mirror 6 in the direction of the guard ring 3.

By providing the second mirror 6, since the light that has conventionally been radiated to the outside of the guard ring 3 and has not contributed to the heating of the guard ring 3 is reflected in the direction of the guard ring 3, the guard ring ( The energy of light irradiated to 3) becomes large. Therefore, the guard ring 3 can be heated efficiently.

Instead of providing the second mirror 6, as shown in FIG. 8, the inclined surface 11a may be provided in the chamber 11, and the inclined surface 11a may be used as a reflective surface.

FIG. 9 shows a structure having a first side wall 4 and a second side wall 5 in which the angle θ1 of the second side wall 5 is 20 °, and the second mirror 6 is provided. The magnitude and distribution of the irradiance of the case. 4, the horizontal axis is the horizontal distance (mm) from the center of the wafer, the vertical axis is the relative value of the irradiance irradiated on the wafer and the guard ring surface, and the range of 0 to 150 mm of the horizontal axis is the area of the wafer W, 150 mm The range of ˜170 mm is the area of the guard ring 3.

In addition, the same figure shows the magnitude and distribution of the irradiance when the angle α of the second mirror 6 is 60 °, 65 °, and when the second mirror 6 is not provided.

As can be seen from FIG. 9, by providing the second mirror 6, the guard ring heating lamps L9 and L10 do not change the distribution of irradiation by the wafer heating lamps L1 to L8. You can change the distribution of the survey. By setting the said angle (alpha) suitably, the quantity from which the light from guard ring heating lamps L9 and L10 is irradiated to the guard ring 3 can be made large.

Fig. 10 shows a conceptual diagram of the irradiance and temperature distribution irradiated with the wafer and the guard ring in the conventional example and the present application.

FIG. 10A is a schematic diagram showing the positions of the wafer W, the guard ring 3, and the holding material 12, and a diagram showing a change in heat capacity. As described above, the difference in heat capacity between the wafer and the guard ring is about 1.5 times.

Fig. 10 (b) is a diagram showing radiation illuminance and temperature when the outputs of the lamps L1 to L10 are the same in the conventional lamp arrangement of Fig. 11.

The irradiance is uniform from the wafer W across the guard ring 3. On the other hand, the temperature becomes uniform because the heat capacity in the wafer surface is equal, but it decreases discontinuously at the part in contact with the guard ring 3 having a large heat capacity, and is attracted by it, thereby decreasing the temperature of the peripheral portion of the wafer W. For this reason, slip occurs in the periphery of the part where temperature fell.

Fig. 10 (c) is a diagram showing radiation illuminance and temperature when only the outputs of the lamps L9 and L10 are enlarged in the conventional lamp arrangement of Fig. 11.

Although the radiation roughness also increases the guard ring portion, the irradiance around the wafer W also increases because the irradiation ring is also irradiated to the wafer W. Thus, the temperature rises as it faces the periphery.

However, the light from the lamps L9 and L10 spreads, and energy cannot be obtained as much as compensating for the heat capacity difference of the guard ring 3, so that the temperature is discontinuously lowered at the portion in contact with the guard ring. Slip occurs at the periphery where this temperature is uneven.

Fig. 10 (d) shows the case of the lamp arrangement and mirror structure of the present invention. Light having a large output power from the lamps L9 and L10 can be concentrated in the guard ring 3. Therefore, the irradiance is increased only in the guard ring portion.

As a result, only the guard ring 3 can be given energy as much as a compensation for the heat capacity difference, and the temperature from the wafer W to the guard ring 3 can be made uniform. As a result, it is possible to prevent the occurrence of slip in the peripheral portion of the wafer. Moreover, since heating can be performed uniformly even at the time of film-forming, a film of uniform thickness can be formed.

As described above, in the present invention, the following effects can be obtained.

(1) Since the light emitted from the guard ring heating lamp was not irradiated to the wafer, the temperature of the wafer did not rise, and uniform heating of the wafer was possible under the control of the wafer heating lamp.

That is, the distance from the guard ring heating lamp to the guard ring is made larger than the distance from the wafer heating lamp to the wafer, and a sidewall with a mirror is provided between the guard ring heating lamp and the wafer heating lamp. Since light emitted from the ring heating lamp is not irradiated to the wafer, even if the input of the guard ring heating lamp is increased, the light is not irradiated to the wafer. Therefore, the temperature of the wafer does not rise, and uniform heating is enabled by the control of the wafer heating lamp.

(2) In addition, since the light previously irradiated in the wafer direction is reflected in the guard ring direction, the energy of the light irradiated to the guard ring is increased. Therefore, the guard ring can be heated efficiently. As a result, the heat capacity of the wafer and the guard ring can be compensated efficiently.

(3) Guard ring can be heated more efficiently by providing a 2nd outer side in the outer periphery of a guard ring heating lamp, and irradiating the guard ring with the light radiated toward the outer periphery of a guard ring.

(4) By providing the second mirror at the outer circumference of the guard ring, the guard ring can be heated more efficiently by irradiating the guard ring with light irradiated around the guard ring.

(5) By the above combination, the wafer can be optically heated at a uniform temperature, and slippage can be prevented from occurring on the wafer.

Moreover, since heating can be performed uniformly even at the time of film-forming, a film of uniform thickness can be formed.

Claims (4)

A plurality of filament lamps having an annular shape and having different diameters of the annular rings are arranged concentrically, and provided with a light source unit provided with a mirror on the rear surface of the filament lamp, In the light irradiation type heat treatment apparatus in which a wafer is disposed on the opposite side of the mirror and a guard ring is provided at the periphery of the wafer, The plurality of filament lamps of the light source unit is composed of a first lamp group provided for the wafer and a second lamp group provided on the outer circumference of the first lamp group and provided for the guard ring, The distance in the light irradiation direction from the lamp of the second lamp group to the guard ring is greater than the distance in the light irradiation direction from the lamp of the first lamp group to the wafer, and the mirror is between the second lamp group and the first lamp group. Light irradiation type heat treatment apparatus characterized in that the side wall is provided by. The method of claim 1, And a second sidewall for reflecting light emitted from the second lamp group in the direction of the guard ring at the outermost circumference of the second lamp group. The method according to claim 1 or 2, And a second mirror for reflecting light emitted from the second lamp group in the direction of the guard ring on the outer circumference of the guard ring. In the light irradiation type heat treatment method in which light irradiated from a plurality of filament lamps is irradiated to a wafer and a guard ring having a different heat capacity from the wafer arranged at the periphery of the wafer, and the wafer is heat treated. The plurality of filament lamps comprises a first lamp group disposed to face the wafer and a second lamp group disposed to face the guard ring, And a wafer is heat-treated, so that light emitted from the second lamp group is not irradiated to the wafer.