JP2002188962A - Radiation temperature measuring device and radiation temperature measuring method and semiconductor manufacturing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radiation temperature measuring device and a radiation temperature measuring method capable of realizing simple radiation temperature measurement, and a semiconductor manufacturing device. SOLUTION: This radiation temperature measuring device including a reflector 5 facing to a wafer 1 is characterized by being equipped with a floodlight 11 for irradiating the face of the wafer 1 facing to the reflector 5 with light I0 having prescribed intensity, and a pyrometer 3 for measuring the intensity of light reflected multiply between the wafer 1 and the reflector 5 before and after irradiation onto the face with light by the floodlight 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radiation temperature measuring device, a radiation temperature measuring method and a semiconductor manufacturing apparatus, and more particularly, to a radiation temperature measuring device for measuring the temperature of an object using a radiation thermometer, and a radiation temperature measuring device. The present invention relates to a measurement method and a semiconductor manufacturing device.

[0002]

2. Description of the Related Art FIG. 1 is a view for explaining a conventional radiation temperature measuring method using a radiation thermometer (pyrometer).
Conventionally, as shown in FIG. 1, there is a method of measuring the temperature of an object using multiple reflection between a wafer 1 to be subjected to temperature measurement and an opposing reflector 5.

That is, the reflectance of the opposing reflector 5 is R, the emissivity of the wafer 1 is ε, and the radiation intensity as a function of temperature is I.
Assuming that _b , the light intensity I measured by the pyrometer 3 is expressed by the following equation (1).

[0004]

(Equation 1) Here, the light intensity I obtained by multiple reflection was measured by pyrometer 3, it is possible to determine the temperature of the wafer 1 as long as it can calculate the radiation intensity I _b from the above equation (1), and the emissivity ε radiation Since the intensity _Ib both depends on the state of the back surface of the wafer 1 and the temperature, the radiation intensity _Ib can be obtained only when the reflectance R of the opposing reflector 5 is 1.

[0005] Therefore, conventionally, the intensity of light multiply reflected respectively in two types of reflector having a reflectance different I _1, to measure the I _2, said intensity I _1, I ₂ Equation (1) by solving a dual simultaneous equations for the emissivity ε and the radiation intensity I _b obtained by substituting into, was the fact that calculating the radiation intensity I _b determining the temperature of the wafer 1. In addition, the above-mentioned binary simultaneous equation is represented by the following equation (2).

[0006]

(Equation 2) FIG. 2 is a diagram showing a configuration of a conventional first radiation temperature measuring device. As shown in FIG. 2, the first conventional radiation temperature measuring device includes a counter reflector 5 having a reflectance R _1.
When, and a counter reflector 7 of the reflectance R _2, which are formed in the recess. Then, the intensity I ₁ of the light multiply reflected between the opposing reflecting plate 5 and the wafer 1 is measured by the pyrometer 3a, the intensity I ₂ of the multiple reflected light between the opposing reflecting plate 7 and the wafer 1 It is measured by the pyrometer 3b.

However, the conventional radiation temperature measuring apparatus as described above has a problem that the apparatus scale and the manufacturing cost increase because two pyrometers 3a and 3b are required.

FIG. 3 is a diagram showing the configuration of a second conventional radiation temperature measuring device. 3 (a) and 3
As shown in (b), the second radiation temperature measuring apparatus in the prior art, the opposing reflecting plate 5 of the radiation temperature measuring device as well as the reflectivity R ₁ shown in FIG. 2, which is formed in the recess reflection including the opposing reflecting plate 7 rate R _2, further comprising a chopper 9 provided in the recess. Here chopper 9 has two rotor blades reflectance consists quadrant slits SL are provided is R ₁ as shown for example in FIG. 3 (c), the rotary blade the recess Has a structure that rotates around the central axis.

Using the radiation temperature measuring device having such a configuration, the temperature is measured as follows. First, FIG.
(A) and FIG. 3 (c), the chopper 9
Is positioned above the path 10, the intensity I ₁ of light that is multiple-reflected between the rotary blade and the wafer 1 and that enters through the slit SL is measured by the pyrometer 3. Next, the rotary wing is rotated 90 degrees, and as shown in FIG. 3B, the intensity I _{2 of} the light that is multiple-reflected between the opposing reflector 7 having the reflectance R ₂ and the wafer 1.
Is measured by the pyrometer 3.

[0010] Then, the radiation intensity _{I b} by solving the simultaneous equations obtained by the intensity _I 1, _{I 2} of the reflectivity _R 1, _{R 2} and measured light are substituted respectively by the above formula (1) Then, the temperature of the wafer 1 is calculated.

However, the conventional radiation temperature measuring device shown in FIG. 3 requires a complicated control mechanism for driving the chopper 9 and measuring the intensity with the pyrometer 3, which increases the size of the device and the manufacturing cost. There is.

[0012]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and provides a radiation temperature measuring apparatus, a radiation temperature measuring method, and a semiconductor manufacturing apparatus which realize simple radiation temperature measurement. The purpose is to:

[0013]

SUMMARY OF THE INVENTION It is an object of the present invention to measure the temperature of an object by measuring the intensity of light multiply reflected between the object and the reflector facing the object. In the method described above, the measurement is performed by measuring the intensity of the multiple reflected light before and after irradiating light to the surface of the object facing the reflector.

According to such means, by irradiating the surface with light, it is possible to measure the intensity of the multiple-reflected light in a state where the reflectance of the reflector changes in a pseudo manner.

Here, the intensity of the light radiated to the surface of the object, the reflectance of the surface of the reflector facing the object, and
The temperature of the object can be easily calculated according to the measured light intensity.

Another object of the present invention is a semiconductor manufacturing apparatus which includes a heating means for heating an object by irradiating light, and performs a predetermined heat treatment on the object, wherein the apparatus is provided so as to face the object. Reflected plate, light irradiation means for irradiating light having a predetermined intensity on the surface of the object facing the reflector,
Before and after the light irradiating unit irradiates the surface with light, a light intensity measuring unit that measures the intensity of light that is multiple-reflected between the object and the reflecting plate, and according to the intensity of the light measured by the light intensity measuring unit, The present invention is attained by providing a semiconductor manufacturing apparatus characterized by comprising a heating control means for controlling a heating means.

According to such a means, the temperature of the object can be easily calculated in accordance with the light intensity measured by the light intensity measuring means. Heat treatment can be performed.

[0018]

Embodiments of the present invention will be described below in detail with reference to the drawings. In the drawings, the same reference numerals indicate the same or corresponding parts.

FIG. 4 is a diagram showing a configuration of a radiation temperature measuring device according to an embodiment of the present invention. As shown in FIG. 4, the radiation temperature measuring device according to the present embodiment has a reflectance R
₁ , a light source 11, a sapphire rod 13, a half mirror 14, and a control unit 15. Here, the control unit 15 incorporates the pyrometer 3 for measuring the intensity of light incident on the sapphire rod 13 and controls the light source 11 to irradiate the wafer 1 via the half mirror 14 and the sapphire rod 13. The intensity I _{0 of} the light to be emitted is adjusted.

[0020] Then, a radiation temperature measuring apparatus having the configuration as described above, by irradiating the light having an intensity I ₀ has the same wavelength as the measurement wavelength pyrometer built into the control unit 15 from the bottom to the wafer 1, As if the opposing reflector 5
The light intensity can be measured with a pyrometer in a state where the reflectance of the sample has changed.

That is, when the light source 11 is turned off, the light intensity measured by the pyrometer is I ₁ , and when the light source 11 is turned on, the light intensity of I ₀ is projected onto the wafer 1 as described above. if the intensity of the light and I _2, can be determined radiation intensity I _b by solving the simultaneous equations obtained from the above equation (1).

[0022] Here, the on-off of the light source 11, measurement timing of intensity I ₁ and the intensity I ₂ by a pyrometer in both states are controlled by the control unit 15 shown in FIG.

In the above, the intensity I _{0 is applied} to the wafer 1.
Assuming that the apparent reflectance of the opposing reflector 5 when the light is projected is R + ΔR (I ₀ ), the light intensities I ₁ ,
The following equation (3) and (4) holds for I _2.

[0024]

(Equation 3) Here, the simultaneous equations consisting of the equation (3) and (4) and solving for the emissivity ε radiation intensity I _b the following formula (5) and (6) is obtained.

[0025]

(Equation 4) Therefore, it is possible to calculate the radiation intensity I _b by the above formula (6), the intensity I ₀ is required to determine the constraints.

Here, the apparent reflectance R + Δ of the opposing reflector 5 when the light of intensity I ₀ is projected on the wafer 1
For R (I ₀ ), R + ΔR = R + I ₀ / I ₂ ≦ 1
Holds. However, as shown in the above expression (4), the intensity I ₂ is represented as a function of the intensity I ₂ itself can not determine the value of the intensity I ₀ from the condition.

Here, the following equation (7) is established from the relationship of intensity I ₂ > intensity I ₁ .

[0028]

(Equation 5) From this, if light having an intensity I ₀ that satisfies the following equation (8) is projected onto the wafer 1, the intensity I ₁ ,
It can be calculated radiation intensity I _b by measuring I _2.

[0029]

(Equation 6) Here, the constraint condition of the above equation (8) is I ₀ ≦ (1-R) I
It can be rewritten as ₁ . Further, the intensity I ₀ of the light projected from the light source 11 to the wafer 1 is set to a value that satisfies the above-described constraint condition by the control unit 15 shown in FIG.

In the following, a more specific structure example of the radiation temperature measuring device shown in FIG. 4 will be described. When measuring the light intensities I ₁ and I ₂ with the pyrometer, as shown in FIG. 4, in order to make it easier to detect the multiple reflected light from the sapphire rod 13, actually, as shown in FIG. It is desirable to provide a concave portion in a portion centered on the sapphire rod 13 on the side. And this recess,
As shown in FIG. 5, it is provided to have a diameter such that pseudo multiple reflection occurs in the concave portion.

Hereinafter, a method of determining the radius r of the concave portion will be described with reference to FIG. The side wall 17 shown in FIG. 5 is made of the same material as the reflection plate 5, and is formed of, for example, aluminum. Further, as described above, the light path 19 connecting the concave portion and the pyrometer can be constituted by a sapphire rod or the like having heat and corrosion resistance.

As shown in FIG. 6, the numerical aperture of the path 19 is sin θ (= NA), the radius of the path 19 is a, the distance between the wafer 1 and the reflector 5 is d, and the depth of the recess is δ. If
The condition under which the light of intensity I ₀ applied to the wafer 1 through the path 19 is multiple-reflected in the concave portion is, for example, the following equation (9).
Can be represented by

[0033]

(Equation 7) Here, tan θ can be expressed by the following formula (10) using the numerical aperture NA according to a mathematical formula.

[0034]

(Equation 8) Thus, the following equation (11) can be obtained by substituting the above equation (10) into the above equation (9).

[0035]

(Equation 9) Therefore, when the above equation (11) is solved for the radius r of the concave portion,
The following equation (12) is obtained.

[0036]

(Equation 10) As described above, by providing the concave portion so that the radius r satisfies the condition of the expression (12), an appropriate radiation temperature measuring device can be configured.

Here, the radius a of the path 19 is determined by the size of the sapphire rod 13, and the distance d between the wafer 1 and the reflector 5 is determined in consideration of the deflection of the wafer 1. The depth δ of the concave portion is set to a value that does not adversely affect the temperature uniformity of the wafer 1. Then, by substituting these parameters for the right side of the equation (12), an appropriate radius r of the concave portion can be specifically determined.

Here, for example, the numerical aperture NA is 0.1
If the radius a is 0.5 mm and the distance d is 5 mm and the depth δ is 1 mm, it is calculated from the equation (12) that the radius r is preferably 1.6 mm or more.

Hereinafter, an example of a semiconductor manufacturing apparatus provided with the above-mentioned radiation temperature measuring device will be described. FIG. 7 shows a rapid heating and heat treatment apparatus (RTP (Rapi)) according to an embodiment of the present invention.
FIG. 2 is a diagram illustrating a configuration of a (d Thermal Process) device). As shown in FIG. 7, the present rapid heating heat treatment apparatus includes a halogen lamp 116, a halogen lamp house 115 for adjusting electric power supplied to the halogen lamp 116, a chamber 117 for heat treating the wafer 1, and a control unit 15. Prepare.

The chamber 117 includes a guard ring 121 for supporting the wafer 1, a quartz support ring 123 for supporting the guard ring 121, and a rotating unit 1 for rotating the guard ring 121 on which the wafer 1 is mounted.
24. And the rotating part 124 is
5, a bearing 127, and a magnet 120 disposed outside the chamber 117.

The chamber 117 is provided with a sapphire rod 13 which detects light emitted from the wafer 1 and is connected to the control unit 15 by an optical fiber. The light source 11 and the light source 11 shown in FIG. Half mirror 1
4 is provided. The inside of the chamber 117 is evacuated.

In the rapid heating and heat treatment apparatus 100 having the above configuration, the wafer 1 is
While being heated by 16, guard ring 121 on which wafer 1 is mounted is rotated by rotating section 124. As a result, the radiated light from the halogen lamp 116 is uniformly applied to the entire surface of the wafer 1,
The uniformity of the temperature distribution of the wafer 1 under the heating is improved as compared with the case where the wafer 1 is not rotated.

Here, the rotating part 124 is made of a magnetic material 125.
Is magnetized by the magnet 120, and the quartz support ring 123 provided with the magnetic body 125 is rotated on the bearing 127 by a magnet coupling that rotates the magnet 120 around the magnetic body 125. Thereby, the guard ring 121 supported by the quartz support ring 123 and mounted with the wafer 1 is rotated on a predetermined surface facing the halogen lamp 116.

As described above, according to the radiation temperature measuring apparatus according to the present embodiment, the temperature of the wafer 1 to be measured can be accurately measured by one pyrometer, so that the apparatus scale and manufacturing cost can be reduced. The radiation temperature measuring device can be provided.

Further, according to the radiation temperature measuring method according to the present embodiment, the light source 11 is switched on and off, and the light intensities I ₁ and I ₂ in both states are measured by one pyrometer, whereby the temperature of the wafer 1 is increased. Can be obtained, so that the temperature of the object can be measured by a simple method.

According to the rapid heating and heat treatment apparatus according to the present embodiment, the temperature of the wafer 1 can be accurately measured by the provided radiation temperature measuring apparatus. be able to.

As described above, according to the radiation temperature measuring apparatus, the radiation temperature measuring method, and the semiconductor manufacturing apparatus according to the present invention, the surface of the object facing the reflector is irradiated with light, so that the object can be simulated. Since the intensity of the multiple-reflected light can be measured in a state where the reflectance of the reflector changes, the temperature of the object can be easily obtained, and thus the object can be easily heat-treated at a predetermined temperature. Can be.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a conventional radiation temperature measurement method using a radiation thermometer.

FIG. 2 is a diagram showing a configuration of a first conventional radiation temperature measuring device.

FIG. 3 is a diagram illustrating a configuration of a second conventional radiation temperature measuring device.

FIG. 4 is a diagram showing a configuration of a radiation temperature measuring device according to an embodiment of the present invention.

5 is a diagram showing a specific structure of the radiation temperature measuring device shown in FIG.

FIG. 6 is an enlarged view showing a specific structure of the radiation temperature measuring device shown in FIG. 5 in an enlarged manner.

FIG. 7 is a diagram showing an overall configuration of a rapid heating and heat treatment apparatus including the radiation temperature measuring apparatus shown in FIG.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 wafer 3, 3a, 3b pyrometer 5, 7 opposed reflector 9 chopper 10, 19 path 11 light source 13 sapphire rod 14 half mirror 15 control unit 17 side wall 100 rapid heat treatment apparatus 121 guard ring 115 halogen lamp house 116 halogen lamp 117 Chamber 120 Magnet 123 Quartz support ring 124 Rotating part 125 Magnetic body 127 Bearing 129 Light emitting part SL Slit

Claims (4)

[Claims] 1. A radiation temperature measuring device including a reflector facing an object, a light irradiating means for irradiating a surface of the object facing the reflector with light having a predetermined intensity, and the light A radiation temperature measuring device, comprising: light intensity measuring means for measuring the intensity of light multiply reflected between the object and the reflector before and after the irradiating means irradiates the surface with the light. 2. A radiation temperature measurement method for measuring the temperature of an object by measuring the intensity of light reflected multiple times between the object and a reflector facing the object, the method comprising: A step of measuring the intensity of the multiple-reflected light before and after irradiating light to a surface of the object facing the reflection plate. 3. The method according to claim 2, wherein the intensity of light applied to the surface of the object, the reflectance of the surface of the reflector facing the object, and the intensity of the light measured in the step. The radiation temperature measuring method according to claim 2, further comprising calculating a temperature of the object. 4. A semiconductor manufacturing apparatus that includes a heating unit that heats an object by irradiating light, and performs a predetermined heat treatment on the object, wherein the reflector is disposed to face the object. Light irradiation means for irradiating light having a predetermined intensity to a surface of the object facing the reflection plate; and before and after the light irradiation means irradiates the light to the surface, the object and the reflection Light intensity measuring means for measuring the intensity of light that has been multiple-reflected between the plates, and heating control means for controlling the heating means according to the intensity of the light measured by the light intensity measuring means. Semiconductor manufacturing equipment.