CN111458951B

CN111458951B - Compound crystal device of deep ultraviolet laser output technology

Info

Publication number: CN111458951B
Application number: CN202010289205.1A
Authority: CN
Inventors: 苏犁; 薛岩; 张红雨; 李池
Original assignee: China University of Geosciences Beijing
Current assignee: China University of Geosciences Beijing
Priority date: 2020-04-14
Filing date: 2020-04-14
Publication date: 2022-03-01
Anticipated expiration: 2040-04-14
Also published as: CN111458951A

Abstract

The invention relates to a composite crystal device of deep ultraviolet laser output technology, which comprises: the first crystal is used for realizing laser up-conversion, up-converting the input 520-538nm pump light and outputting 700-735nm laser light; the second crystal is used for realizing the frequency combination of the laser, the frequency combination of the 700-minus 735nm laser and 259.4-288.2nm generated by the frequency doubling of the 520-minus 538nm laser is carried out, and the 190-minus 205nm deep ultraviolet laser is output; wherein the first crystal and the second crystal are coaxially connected to form a unified member. The invention can convert the input 520-538nm pump laser into 190-205nm deep ultraviolet laser through the nonlinear effect for output, and has the advantages of complete laser form, stable energy and lower component cost.

Description

Compound crystal device of deep ultraviolet laser output technology

Technical Field

The invention relates to the technical field of laser composite crystals, in particular to a composite crystal device of a deep ultraviolet laser output technology.

Background

Laser frequency conversion is a nonlinear optical technology used for realizing stable output of laser equipment by specific and different frequencies, the existing mature technology realizes laser frequency conversion, for example, 1064nm laser 2 generated by crystal excitation is frequency-doubled to form 512nm laser, 3 frequency-doubled to form 266nm laser, etc., and the laser equipment in green light, ultraviolet and deep ultraviolet regions is produced by frequency-doubling 2, 3 frequency-doubling and frequency-changing technologies such as 4 frequency-doubling, 5 frequency-doubling, etc. superposed with other laser frequency-changing technologies. By means of laser frequency conversion technology, laser with specific function and specific wavelength and industrial and scientific research equipment may be manufactured. Along with the urgent needs of high-speed development of the electronic industry, scientific research on sample micro-area sampling analysis and the like, research and development of micron-sized etching lasers which can be used for precise sampling of solid sample micro-areas and no micro damage to silicon crystal plates are highly concerned, and 193nm and other deep ultraviolet area lasers become laser types with the best application prospect due to the excellent performances of low thermal efficiency, strong and stable etching capability, very small transmission energy loss in a room temperature environment and the like.

At present, 193nm lasers also widely use the technology of directly generating 193nm laser by ArF excimer gas excitation, and have the problems of high manufacturing price, high use and operation cost, strict requirements on placement environment, over-strong instantaneous output energy and large fluctuation, which are difficult to overcome. Compared with the multi-frequency solid 193nm laser, the multi-frequency solid 193nm laser has the advantages of low price and use cost of the whole laser, relatively small volume of the whole laser, convenient use and proper and stable instantaneous laser energy output, and the multi-frequency solid 193nm laser which is continuously improved in technology is expected to become special equipment for low-damage micro-area (micron-scale) etching and scientific sampling which are urgently needed by various industries. Therefore, the technology of converting the visible light region laser (266nm, 532nm, etc.) formed by simple frequency conversion into the stable output 193nm deep ultraviolet laser becomes the key.

Disclosure of Invention

In view of the above problems, the present invention provides a composite crystal device capable of converting the input pump laser light of 520-.

In order to achieve the purpose, the invention adopts the following technical scheme: a composite crystal device of deep ultraviolet laser output technology, the composite crystal device comprising:

the first crystal is used for up-converting the input 520-538nm pump light and outputting 700-735nm laser;

the second crystal is used for combining the input 700-735nm laser with the input 259.4-288.2nm laser and outputting 190-205nm deep ultraviolet laser; wherein the first crystal and the second crystal are coaxially connected.

Further, the first crystal adopts a KTiOPO4 crystal.

Further, b-BaBO4 crystal is adopted as the second crystal.

Further, the laser of the first crystal enters the antireflection film with the side surface plated with 520-538nm and the high-reflection film with the side surface plated with 700-735 nm; the laser output side of the first crystal is plated with an antireflection film with the wavelength of 520-538nm and a semi-reflecting and semi-transparent film with the transmittance of 70% with the wavelength of 700-735 nm.

Furthermore, the laser input side surface of the second crystal is plated with an antireflection film with the wavelength of 520-.

Further, the first crystal and the second crystal adopt a rectangular structure with the same cross section.

Further, the device also comprises an optical adjusting frame, wherein the optical adjusting frame comprises an adjusting frame body, an adjusting plate and a positioning hole plate; the adjusting frame body center sets up the regulating plate, the regulating plate center is provided with and is used for placing the circular mounting hole of locating hole, the locating hole board be used for placing by the compound crystal that first crystal and second crystal constitute.

Further, the adjusting bracket body comprises a rectangular frame and an L-shaped frame;

the adjusting plate is arranged in the rectangular frame;

the L-shaped frame is provided with two first adjusting screw rods, and the two first adjusting screw rods are arranged at two end parts of the L-shaped frame, are used for connecting the rectangular frame and are used for adjusting the distance between the rectangular frame and the L-shaped frame;

the rectangular frame is provided with two second adjusting screw rods, the two second adjusting screw rods are arranged on the adjacent side surfaces of the rectangular frame and penetrate through the rectangular frame to be connected with the adjusting plate for respectively adjusting the positions of the adjusting plate;

when the compound crystal adjusting device is used, the position and the angle of the compound crystal are adjusted by adjusting the first adjusting screw and the second adjusting screw.

Further, the locating hole plate comprises a substrate, a convex edge structure is arranged on one side of the substrate, and a U-shaped locating frame for placing the composite crystal is arranged on the outer side of the convex edge structure.

Due to the adoption of the technical scheme, the invention has the following advantages: the composite crystal device of the deep ultraviolet laser output technology can convert input pump laser with the wavelength of 520-538nm into deep ultraviolet laser with the wavelength of 190-205nm through a nonlinear effect to output, has low cost, integrates multi-stage frequency conversion into one device, effectively reduces the problems of poor stability of frequency conversion output 193nm laser caused by factors such as temperature and vibration of equipment placing environment and the like, and can facilitate the adjustment and the calibration of the use process of a laser.

Drawings

The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the invention. Like reference numerals refer to like parts throughout the drawings. In the drawings:

FIG. 1 is a schematic diagram of a deep ultraviolet laser output composite crystal structure according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of a deep ultraviolet laser output composite crystal structure according to an embodiment of the present invention;

FIG. 3 is a schematic view of an optical alignment mount structure according to an embodiment of the present invention;

FIG. 4 is a schematic view of an optical alignment mount structure according to an embodiment of the present invention;

FIG. 5 is a schematic diagram of a positioning hole plate structure according to an embodiment of the invention;

FIG. 6 is a schematic view of a composite crystal of an embodiment of the present invention mounted on a positioning orifice plate.

Detailed Description

Exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention can be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

It is to be understood that the terminology used herein is for the purpose of describing particular example embodiments only, and is not intended to be limiting. As used herein, the singular forms "a", "an" and "the" may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprises," "comprising," "including," and "having" are inclusive and therefore specify the presence of stated features, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and/or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order described or illustrated, unless specifically identified as an order of performance. It should also be understood that additional or alternative steps may be used.

Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as "first," "second," and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.

For convenience of description, spatially relative terms, such as "inner", "outer", "lower", "upper", and the like, may be used herein to describe one element or feature's relationship to another element or feature as illustrated in the figures. Such spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures.

As shown in fig. 1 and fig. 2, the composite crystal device of the deep ultraviolet laser output technology provided in this embodiment includes:

the first crystal a is used to realize laser upconversion, that is, upconversion of the laterally input 520-.

The second crystal B is used for realizing laser frequency combination, namely, the frequency combination is carried out on the 700-735nm laser which is converted and output on the first crystal A and the 259.4-288.2nm laser which is longitudinally input, and the 190-205nm deep ultraviolet laser is output; the 259.4-288.2nm laser can be generated by frequency doubling with 520-538nm laser, and is not limited in particular. Specific principle examples of the second crystal B are, for example: the 1064nm laser frequency doubling generated by the excitation of the Nd-garnet crystal is divided into two paths of e light with the wavelength of 714.1nm generated by the o light pump with the wavelength of 520nm, and then the e light with the wavelength of 714.1nm and the o light with the wavelength of 520nm are frequency doubled to generate the e light with the wavelength of 260nm and the o light with the wavelength of 192 nm.

The first crystal A and the second crystal B are coaxially arranged and directly fixedly connected, the first crystal A can adopt a KTiOPO4 (titanium potassium phosphate) crystal, and the second crystal B can adopt a B-BaBO4 (barium borate) crystal.

In some embodiments of the invention, the laser entrance side surface a1 of the first crystal a is plated with an antireflection film of 520-538nm and a high-reflection film of 700-735 nm; the laser output side surface A2 of the first crystal A is plated with an antireflection film with 520-538nm transmittance and a semi-reflective semi-transparent film with 70% transmittance with 700-735nm transmittance, so that the transmitted laser intensity with 700-735nm transmittance is effectively improved.

In some embodiments of the invention, the laser input side surface B1 of the second crystal B is plated with an antireflection film of 520-538nm and an antireflection film of 700-735nm, and the laser output side surface B2 of the second crystal B is plated with an antireflection film of 520-538nm and an antireflection film of 190-205nm and a high-reflection film of 700-735nm, so as to effectively ensure the input amount of the laser of 520-538nm and filter back the remaining laser of 700-735nm in the process of generating the laser of 193nm, so that the 193nm laser with uniform and stable energy generated by mixing, i.e. the 193nm laser spot is ensured to have the optimal form.

In some embodiments of the present invention, the first crystal a and the second crystal B may adopt a rectangular structure, the lengths of the first crystal a and the second crystal B are not limited, but the cross sections of the two crystals have the same size, and the two crystals may be directly connected by end face butting to generate and output 190-205nm deep ultraviolet laser.

In some embodiments of the present invention, the composite crystal device of the deep ultraviolet laser output technology may further include an optical adjusting bracket, where the optical adjusting bracket is used to place a composite crystal formed by the first crystal a and the second crystal B, and in use, the angle and the position of the composite crystal may be adjusted by the optical adjusting bracket. It should be noted that the optical adjusting rack may adopt the adjusting rack of the prior art to place and adjust the position and angle of the composite crystal, and the structure of the optical adjusting rack is not limited by the present invention.

Preferably, as shown in fig. 3 to 6, the present embodiment provides an optical adjustment frame for placing a composite crystal, and is not limited thereto.

The optical adjusting rack of the embodiment comprises an adjusting rack body 1, an adjusting plate 2 and a positioning orifice plate 3. The adjusting plate 2 is arranged at the center of the adjusting frame body 1, the circular mounting hole for placing the positioning hole plate 3 is formed in the center of the adjusting plate 2, and the positioning hole plate 3 is used for placing the composite crystal.

The adjusting frame body 1 comprises a rectangular frame 11 and an L-shaped frame 12, an adjusting plate 2 is placed inside the rectangular frame 11, and a circular mounting hole is formed in the center of the adjusting plate 2 and used for mounting the positioning hole plate 3. The L-shaped frame 12 is provided with two first adjusting screws 13, and the two first adjusting screws 13 are arranged at two ends (diagonal lines) of the L-shaped frame 12 and used for connecting the rectangular frame 11 and adjusting the distance between the position of the rectangular frame 11 and the L-shaped frame 12. The rectangular frame 11 is provided with two second adjusting screws 14, and the second adjusting screws 14 are arranged on the adjacent side surfaces of the rectangular frame 11, penetrate through the rectangular frame 11 and are connected with the adjusting plate 2 to be used for respectively adjusting the upper position, the lower position, the left position and the right position of the adjusting plate 12.

The positioning hole plate 3 comprises a substrate 31, a convex edge structure 32 is arranged on one side of the substrate 31, and a U-shaped positioning frame 33 is arranged on the outer side of the convex edge structure 32 and used for positioning and installing the composite crystal therein to conveniently adjust and regulate the composite crystal so as to adapt to the needs of work.

During the use, through can adjusting first adjusting screw 13 and second adjusting screw 14, realize the position and the angle modulation of regulating plate 2 in the equidirectional not to the realization is to the regulation of location orifice plate 3, and then adjusts compound crystal's position and angle, in order to satisfy operation requirement.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solutions of the present invention and not for limiting the same, and although the present invention is described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that: modifications and equivalents may be made to the embodiments of the invention without departing from the spirit and scope of the invention, which is to be covered by the claims.

Claims

1. A composite crystal device for deep ultraviolet laser output technology, the composite crystal device comprising:

the second crystal is used for combining the input 700-735nm laser with the input 259.4-288.2nm laser and outputting 190-205nm deep ultraviolet laser; wherein the first crystal and the second crystal are coaxially connected;

the optical adjusting frame comprises an adjusting frame body, an adjusting plate and a positioning hole plate; the adjusting plate is arranged at the center of the adjusting frame body, a circular mounting hole for placing the positioning hole plate is formed in the center of the adjusting plate, and the positioning hole plate is used for placing a composite crystal formed by the first crystal and the second crystal;

the adjusting frame body comprises a rectangular frame and an L-shaped frame;

the adjusting plate is arranged in the rectangular frame;

2. The deep ultraviolet laser output technology composite crystal device as set forth in claim 1, wherein said first crystal is a KTiOPO4 crystal.

3. The deep ultraviolet laser output technology composite crystal device as set forth in claim 1, wherein the second crystal is a b-BaBO4 crystal.

4. The composite crystal device of the deep ultraviolet laser output technology as claimed in any one of claims 1 to 3, wherein the laser of the first crystal enters the anti-reflection film with a side surface of 520-538nm and the high reflection film with a side surface of 700-735 nm; the laser output side of the first crystal is plated with an antireflection film with the wavelength of 520-538nm and a semi-reflecting and semi-transparent film with the transmittance of 70% with the wavelength of 700-735 nm.

5. The composite crystal device of the deep ultraviolet laser output technology as claimed in any one of claims 1 to 3, wherein the laser input side of the second crystal is plated with an antireflection film with a wavelength of 520-538nm and an antireflection film with a wavelength of 700-735nm, and the laser output side of the second crystal is plated with an antireflection film with a wavelength of 520-538nm, an antireflection film with a wavelength of 190-205nm and a high-reflection film with a wavelength of 700-735 nm.

6. The deep ultraviolet laser output technology composite crystal device as set forth in any one of claims 1 to 3, wherein the first crystal and the second crystal have a rectangular structure with the same cross section.

7. The deep ultraviolet laser output technology composite crystal device as claimed in claim 1, wherein the positioning hole plate comprises a substrate, a protruding edge structure is arranged on one side of the substrate, and a U-shaped positioning frame for placing the composite crystal is arranged on the outer side of the protruding edge structure.