JPH11118704A - Durability inspecting device and pulsed light irradiating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten inspection time in a durability inspection substantially. SOLUTION: A pulsed light source 11 sequentially and repeatedly generates pulsed light. A repetition number increasing part 12 divides pulsed light from the pulsed light source 11 into a plurality of pieces, and the whole or a portion of a plurality of pieces of pulsed light among a plurality of pieces of divided pulsed light is synthesized by time-delaying at least a portion of divided light so as not to coincide with one another in time to create pulsed light in which the number of repetition in a unit of time is increased with respect to pulses light from the pulsed light source 11 and each peak quantity of light is approximately the same. An object to be inspected 13 is irradiated with the created pulsed light.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a durability test apparatus for performing a durability test on an object to be inspected, such as an optical component or an optical device, by sequentially and repeatedly irradiating the object with pulsed light, and a durability inspection apparatus used therefor. And a pulsed light irradiation device.

[0002]

2. Description of the Related Art An exposure apparatus using a laser beam or the like for manufacturing a semiconductor, a laser CVD apparatus, a laser annealing apparatus, a laser doping apparatus, a laser microscope, a laser drawing apparatus,
The laser welding apparatus, its components (for example, light receiving elements, lenses, mirrors, liquid crystal elements, and their packages), various other optical components and optical devices, and the like are deteriorated by laser light or the like ( For example, the durability of the lens is deteriorated or the resin used for the package is deteriorated.) The durability test is performed by sequentially and repeatedly irradiating the inspection object with pulsed light.

[0005] FIG. 5 is a schematic configuration diagram of a conventional durability inspection apparatus.
Shown in This conventional durability inspection apparatus includes a laser light source 1 as a pulse light source that sequentially and repeatedly generates pulse light, and the pulse light generated by the laser light source 1 is applied to an object 2 to be inspected. ing.

[0004]

However, the conventional durability inspection apparatus has a disadvantage that an extremely long inspection time is required.

[0005] That is, the durability test is performed in two hours of the actual use time.
It takes 10 to 10 times longer and then the inspection target 2
To evaluate. Therefore, in the conventional durability inspection apparatus, if the actual use time of the inspection target 2 is, for example, one year, the inspection time is a long period of 2 to 10 years.

At this time, if the pulse intensity (peak light quantity) per pulse of the pulse light applied to the inspection target 2 is the same as that in actual use, the durability of the inspection target 2 is determined by the number of applied pulses. Is determined. Therefore, if the pulse light generation frequency of the laser light source 1 can be made higher than the frequency of the pulse light applied to the inspection target 2 during actual use, the inspection time of the durability inspection is shortened in inverse proportion to the frequency. be able to. However, there is a limit in increasing the pulse light generation frequency of the laser light source 1, and the frequency cannot be significantly increased. Therefore, after all, the inspection time cannot be reduced so much, and a very long inspection time is still required.

[0007] The present invention has been made in view of such circumstances, and provides a durability inspection apparatus capable of greatly reducing the inspection time of the durability inspection, and a pulse light irradiation apparatus that can be used for the durability inspection apparatus. The purpose is to provide.

[0008]

In order to solve the above-mentioned problems, a durability inspection apparatus according to a first aspect of the present invention repeatedly irradiates an object to be inspected with pulsed light sequentially and repeatedly. A durability inspection apparatus for performing inspection, comprising: a pulse light source that sequentially generates pulsed light; a pulse light source that divides the pulse light from the pulse light source into a plurality of pieces; and all or one of the plurality of divided pulse lights. The plurality of pulsed lights of the unit are synthesized by giving a time delay to at least a part thereof so as not to overlap each other in time, and the number of repetitions per unit time increases as compared with the pulsed light from the pulsed light source. Means for increasing the number of repetitions for generating pulsed light having substantially the same peak light amount, and irradiating the inspection object with the pulsed light generated by the means for increasing the number of repetitions. Is shall.

According to the first aspect, unlike the conventional durability inspection apparatus, the object to be inspected is not directly irradiated with the pulse light generated by the pulse light source, but is applied to the pulse light generated by the pulse light source. The object to be inspected is irradiated with the pulse light generated by the repetition number increasing means based on the pulse number, the pulse light having an increased number of repetitions per unit time. The means for increasing the number of repetitions divides the pulsed light from the pulsed light source into a plurality of light beams, and at least one of the divided plurality of the pulsed light beams so that they do not temporally overlap each other. The pulse number generated by the repetition number increasing means and applied to the object to be inspected is determined by the number of repetitions per unit time of the pulse light generated by the pulse light source. More than twice.

As described above, according to the first aspect, the pulse light having the number of repetitions per unit time that is twice or more the number of repetitions per unit time of the pulse light generated by the pulse light source is received. Since irradiation can be performed on the inspection target, the inspection time can be significantly reduced.

Since the means for increasing the number of repetitions generates pulse light as described above, the peak light quantity of the generated pulse light is lower than the peak light quantity of the pulse light generated by the pulse light source. . Therefore, for example, by using a pulse light source having a sufficiently high peak light quantity of the generated pulse light, for example, the peak light quantity of the pulse light generated by the repetition number increasing means is reduced to the peak light quantity of the pulse light irradiated to the inspection object in actual use. It may be made to substantially match with.

Incidentally, in order to increase the inspection accuracy of the durability inspection, the durability inspection should be performed in a state as close as possible to the state in actual use. However, at the time of the durability test, if each of the pulse lights applied to the object to be inspected overlaps with each other in time, or if the peak light amounts of the pulse lights applied to the object to be inspected are greatly different from each other, the actual situation may occur. Since it is far from the state at the time of use, the inspection accuracy of the durability test is reduced. In this regard, according to the first aspect, the pulse lights irradiated on the inspection target do not overlap with each other in time, and the peak light amounts of the pulse lights irradiated on the inspection target are substantially the same. Therefore, the inspection accuracy of the durability inspection is increased.

The time interval of the pulse light generated by the repetition number increasing means may or may not be the same for all the pulse lights. This applies to a second embodiment of the present invention described later.

According to a second aspect of the present invention, there is provided a pulsed light irradiating apparatus comprising: a pulsed light source for sequentially and repeatedly generating pulsed light; and a plurality of divided pulsed lights from the pulsed light source. All or some of the plurality of pulsed lights are synthesized by giving a time delay to at least a part thereof so as not to overlap with each other, and the number of repetitions per unit time is the pulsed light from the pulsed light source. Means for increasing the number of repetitions for generating pulsed light that is increased compared to
And irradiating the irradiation target with the pulsed light generated by the repetition number increasing means.

The pulse light irradiation device according to the second embodiment can be used as the durability inspection device according to the first embodiment, but is not limited to its use.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A durability inspection apparatus according to one embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 is a schematic configuration diagram showing a durability inspection apparatus according to the present embodiment. FIG. 2A is a diagram illustrating pulse light generated by the pulse light source 11 in FIG. 1, and FIG. 2B is a diagram illustrating pulse light generated by the repetition number increasing unit 12 in FIG. In FIGS. 2A and 2B, the vertical axis indicates the light amount, and the horizontal axis indicates time. FIG. 3 is a schematic configuration diagram showing an example of the optical delay units 22 to 24 in FIG.

The durability inspection apparatus according to the present embodiment includes a pulse light source 11 for sequentially and repeatedly generating a pulse light, and a repetition number increasing unit 12.
The inspection object 13 is irradiated with the pulse light generated in Step 2.

In the present embodiment, an excimer laser light source is used as the pulse light source 11. The object 13 to be inspected may be any of various optical devices using excimer laser light (for example, an exposure device, a laser CVD device, a laser annealing device, a laser doping device, a laser microscope, a laser drawing device, a laser welding device, or the like), or (For example, a light receiving element, a lens, a mirror, a liquid crystal element, a package thereof, and the like). However, in the present invention, the pulse light source 11 is not limited to the excimer laser light source, and the object 13 to be inspected is not limited to the above example.

The excimer laser light emitted from the excimer laser light source usually has an oscillation frequency of 10 ¹ to 10 ^3.
Hz, energy per pulse is 10 ¹ to 10 ³
The excimer laser light source is a pulse light source that generates extremely powerful light in a very short time, with a time width (half width) of mJ and one pulse being about 10 ns.

The number-of-repetitions increasing unit 12 divides the pulse light from the pulse light source 11 into a plurality of pulses, and divides all or some of the plurality of divided pulse lights with respect to time. A time delay is given to at least a part of the pulse light so as not to be overlapped, and the pulse light whose repetition number per unit time is increased as compared with the pulse light from the pulse light source and whose peak light amounts are substantially the same is obtained. Generate.

In this embodiment, the number-of-repetitions increasing unit 1
2, half mirrors 14 to 19, as shown in FIG.
It comprises total reflection mirrors 20, 21 and optical delay units 22 to 24.

As shown in FIG. 3, each of the optical delay units 22 to 24 is composed of total reflection mirrors 31 to 34. In the optical delay units 22 to 24, the light traveling rightward in FIG. 3 and entering the total reflection mirror 31 is reflected by the total reflection mirror 31, and further reflected between the total reflection mirror 32 and the total reflection mirror 33. Repeat the reflection zigzag multiple times. Thereafter, this light is reflected by the total reflection mirror 34 and travels rightward in FIG. Therefore, each of the optical delay units 22 to 24 delays the incident light by increasing the optical path length. In the present embodiment, the delay time of each of the optical delay units 22 to 24 is set to ΔT which is considerably smaller than the period T of the pulse light generated by the pulse light source 11. However, the delay time of each of the optical delay units 22 to 24 is not limited to this, and may be set to another delay time, and it is not necessary that all of the optical delay units have the same delay time.

The half mirrors 14, 16, and 18 each constitute an optical splitter, and the half mirrors 15, 17, and 19 each constitute an optical mixer (light combiner).

In this embodiment, the pulse light generated by the pulse light source 11 is incident on the half mirror 14 and is divided into light transmitted through the half mirror 14 and light reflected by the half mirror 14. The light reflected by the half mirror 14 is reflected by the total reflection mirror 20, is given a delay time ΔT by the optical delay unit 22, and is incident on the half mirror 16. The light incident on the half mirror 16 is split into light reflected by the half mirror 16 and light transmitted through the half mirror 16. The light reflected by the half mirror 16 is combined with the light transmitted through the half mirror 14 by the half mirror 15, and the combined light travels to the half mirror 17. Half mirror 16
Is transmitted to the half mirror 18 after being given a delay time ΔT by the optical delay unit 23. The light incident on the half mirror 18 is split into light reflected by the half mirror 18 and light transmitted through the half mirror 18. The light reflected by the half mirror 18 is combined with the combined light emitted from the half mirror 15 by the half mirror 17, and the combined light is combined with the half mirror 1.
Go to 9. The light transmitted through the half mirror 18 is reflected by the total reflection mirror 21 after being given a delay time ΔT by the optical delay unit 24. The light reflected by the total reflection mirror 21 is combined with the combined light emitted from the half mirror 17 by the half mirror 19, and is directed toward the inspection target 13 as pulse light generated by the repetition number increasing unit 12. Is emitted.

With the above operation, based on the pulse light shown in FIG.
The pulse light shown in FIG. 2B is obtained from the repetition number increasing unit 12, and the pulse light shown in FIG.
Is irradiated.

In FIG. 2A, P0 is a pulse light source 1
1 shows the individual pulses of the pulsed light generated. FIG.
In (b), P1 to P4 indicate individual pulses of the pulse light generated by the pulse light source 11. A total of four pulses P1 to P4 are generated from one pulse P0. The pulse P1 corresponds to a pulsed light passing through the path of 11 → 14 → 15 → 17 → 19, and the pulse P2 corresponds to 11 → 14 → 20
→ 22 → 16 → 15 → 17 → 19 The pulse P3 corresponds to 11 → 14 → 20 → 22 →
The pulse light corresponds to the pulse light passing through the path of 16 → 23 → 18 → 17 → 19, and the pulse P4 is 11 → 14 → 20 → 22 → 1
It can be seen that the pulsed light beams P1 to P4 are synthesized so as not to temporally overlap with each other, corresponding to the pulsed light beams passing through the route of 6 → 23 → 18 → 24 → 21 → 19. Therefore, the number of repetitions per unit time of the pulse light (FIG. 2B) applied to the inspection target 13 is the number of repetitions per unit time of the pulse light (FIG. 2A) generated by the pulse light source 11. It is four times as large.

In this embodiment, the transmittance of the half mirror 14 is 1/3 (33%) and the half mirror 15
Is 1/3 (33%), the transmittance of the half mirror 16 is 3/4 (75%), and the transmittance of the half mirror 17 is 3
/ 4 (75%), the transmittance of the half mirror 18 is 1/3
(33%), the transmittance of the half mirror 19 is 2/3 (67
%). As a result, as shown in FIG. 2B, the peak light amounts of the respective pulses P1 to P4 become approximately 1/18 of the peak light amount of the original pulse P0 and are equal to each other.

According to the present embodiment, unlike the conventional durability inspection apparatus shown in FIG. 5, the pulse light (FIG. 2A) generated by the pulse light source 11 is directly applied to the inspection object 13. Instead, the pulse light generated by the repetition number increasing unit 12 based on the pulse light (FIG. 2A) generated by the pulse light source 11 and having the repetition number per unit time quadrupled ( FIG. 2B irradiates the inspection target 13. Therefore, according to the present embodiment, the inspection time of the durability inspection can be significantly reduced.

Further, according to the present embodiment, each of the pulses P1 to P4 of the pulse light (FIG. 2B) applied to the inspection target 13 does not overlap with time, and Since the peak light amounts of the respective pulses P1 to P4 of the irradiated pulse light (FIG. 2B) are substantially the same, the inspection accuracy of the durability inspection is increased.

Next, a durability test apparatus according to another embodiment of the present invention will be described with reference to FIG.

FIG. 4A is a schematic perspective view showing the durability test apparatus according to the present embodiment, and FIG. 4B is a schematic plan view seen from the height direction. 4, elements that are the same as or correspond to elements in FIG. 1 are given the same reference numerals, and descriptions thereof are omitted.

The only difference between the durability test apparatus according to the present embodiment and the durability test apparatus shown in FIG.

In the present embodiment, the number-of-repetitions increasing unit 1
Reference numeral 2 denotes two mirror boxes 41 and 42 and four total reflection mirrors 43 to 46. The mirror boxes 41 and 42 are configured as hollow rectangular parallelepipeds having the same shape and size.

The four side walls 41a of the mirror box 41,
Inner surfaces of 41b, 41c, 41d and mirror box 42
The inner surfaces of the four side walls 42a, 42b, 42c, 42d are basically total reflection mirrors. The mirror boxes 41 and 42 include the straight line L in FIG.
They are arranged so as to be plane-symmetric with respect to a plane perpendicular to the plane of FIG.

The pulse light (same as the pulse light shown in FIG. 2A) generated by the pulse light source 11 is incident on the middle point in the width direction of the side wall 41d above the side wall 41d of the mirror box 41. A total transmission window 51 (a simple opening or a transparent member) may be formed. This pulse light passes through the total transmission window 51,
The light is incident so as to reach a predetermined position at a midpoint position in the width direction of the side wall 41 a and lower than the total transmission window 51. The incident optical path of the pulse light is such that when projected on the paper surface of FIG.
Is arranged.

The half mirror portion 5 is partially formed on the side wall 41a.
2 to 54 and the total transmission window 55 are formed, but assuming that these are not formed, the pulse light incident from the total transmission window 51 is sequentially shifted downward, and the side walls 41a → the side walls 41b → the side walls 41c → Side wall 41d → side wall 41a →
In this order, the light is totally reflected by these side walls in order and forms an optical path such as a spiral deformed into a rhombus. The half mirror section 52 is configured such that the pulse light incident from the total transmission window 51
1a, it is formed at the position where it is reflected for the second time. The half mirror portion 53 is formed at a position where the pulse light incident from the total transmission window 51 is reflected on the side wall 41a for the fourth time. The half mirror portion 54 is formed at a position where the pulse light incident from the total transmission window 51 is reflected on the side wall 41a for the sixth time. The total transmission window 55 is formed at a position where the pulse light incident from the total transmission window 51 reaches the eighth time on the side wall 41a.

Accordingly, a part of the light is split from each of the half mirror portions 52 to 54 and emitted to the outside, and the remaining light is emitted to the outside from the total transmission window 55. The optical paths of these emitted lights are parallel to the incident optical path of the pulse light,
When projected onto the paper surface of FIG. 4 (b), it forms the same straight line as the incident light path of the pulse light.

Half mirror sections 52 to 54 and total transmission window 5
5 includes a straight line L in FIG.
The total reflection mirrors 43 to 46 are respectively arranged in parallel with the paper surface of FIG. 4B at the positions reaching the planes perpendicular to the paper surface of FIG.

At a position that is plane-symmetric with respect to the planes including the straight line L in FIG. 4B and perpendicular to the plane of FIG.
In the mirror box 42, all transmission windows 61 and 65 and half mirror portions 62 to 64 are respectively formed. Therefore, each light reflected by the total reflection mirrors 43 to 46 is
The half mirror portions 62 to 64 and the total transmission window 65 enter the mirror box 42, are synthesized in the mirror box 42, and are generated from the total transmission window 61 as pulse light generated by the repetition number increasing unit 12. 13 is emitted.

With the above operation, in the present embodiment, as in the above-described embodiment, the pulse light source 11 generates the pulse light shown in FIG.
The pulse light shown in FIG. 2B is obtained from the repetition number increasing unit 12, and the pulse light shown in FIG.
Is irradiated.

In the present embodiment, the pulse P1 in FIG. 2B corresponds to the pulse light passing through the total reflection mirror 43,
The pulse light P2 corresponds to the pulse light passing through the total reflection mirror 44, the pulse light P3 corresponds to the pulse light passing through the total reflection mirror 45, and the pulse light P4 corresponds to the pulse light passing through the total reflection mirror 46. ing.

In this embodiment, the transmittances of the half mirror sections 52 to 54 and 62 to 64 are determined by the respective pulses P1 to P1.
4 are set to be equal.

Therefore, the present embodiment also provides the same advantages as the above-described embodiment.

Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments.

In each of the above-described embodiments, the pulse light source 11 and the repetition number increasing unit 12 use the pulse light generated by the repetition number increasing unit 12 (FIG. 2).
This constitutes a pulsed light irradiation device that irradiates (b)) to the irradiation target. In each of the above-described embodiments, these pulse light irradiation devices are used for the durability test. However, the pulse light irradiation device can be used for various other applications.

[0047]

As described above, according to the present invention, it is possible to drastically shorten the inspection time of the durability inspection and to obtain a high-accuracy durability inspection apparatus, and a pulse which can be used in the apparatus. A light irradiation device can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing a durability inspection apparatus according to an embodiment of the present invention.

2A and 2B are diagrams showing pulsed light of each part in the durability test apparatus shown in FIG. 1, FIG. 2A is a diagram showing pulsed light generated by a pulse light source in FIG. 1, and FIG. FIG. 2 is a diagram illustrating pulse light generated by a repetition number increasing unit in FIG. 1.

FIG. 3 is a schematic configuration diagram illustrating an example of an optical delay unit in FIG. 1;

FIG. 4 is a view showing a durability test apparatus according to another embodiment of the present invention, and FIG. 4 (a) is a schematic perspective view thereof, FIG.
(B) is a schematic plan view thereof.

FIG. 5 is a schematic configuration diagram of a conventional durability inspection apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Pulse light source 12 Repetition number increase part 13 Inspection object 14-19 Half mirror 20,21 Total reflection mirror 22-24 Optical delay device 31-34 Total reflection mirror 41,42 Mirror box 43-46 Total reflection mirror 51,55, 61,65 Total transmission window 52-54,62-64 Half mirror part

Claims (2)

[Claims] 1. A durability inspection apparatus for sequentially and repeatedly irradiating an object to be inspected with pulsed light to perform a durability inspection of the object to be inspected, comprising: a pulsed light source for sequentially and repeatedly generating pulsed light; The pulsed light from the light source is divided into a plurality of pulses, and all or some of the divided plurality of pulsed lights are given a time delay at least in part so as not to overlap each other in time. Means for increasing the number of repetitions per unit time as compared with the pulse light from the pulse light source and generating pulse light having substantially the same peak light amount. A durability inspection apparatus, wherein the pulse light generated by the number-of-times increasing means is applied to the object to be inspected. 2. A pulse light source that sequentially generates pulse light repeatedly, and divides the pulse light from the pulse light source into a plurality of light beams, and all or a part of the plurality of divided pulse light beams. Are synthesized by giving a time delay to at least a part of them so that they do not overlap with each other, and the number of repetitions per unit time increases as compared with the pulsed light from the pulsed light source, and each peak light amount is substantially reduced. A pulse light irradiation apparatus, comprising: a repetition number increasing unit that generates the same pulse light; and irradiating the irradiation target with the pulse light generated by the repetition number increasing unit.