CN104701724A - Dual optical path device for connecting pulse laser with terminal experiment cavity - Google Patents

Abstract

The invention discloses a dual optical path device connecting a pulse laser and a terminal experiment cavity. The device (12) is connected with a pulse laser (11), a film deposition system (13) and a vacuum glove box (14). The model of the pulse laser 11 is PRO-320Nd:YAG, and the dual optical path device (12) is composed of seven dielectric film mirrors, one focusing mirror, corresponding mirror frames and optical path protection equipment. The two optical paths correspond to lasers with wavelengths of 1064nm and 532nm respectively, among which the invisible infrared light with a wavelength of 1064nm reaches the reaction furnace through three mirrors and one focusing mirror respectively; the visible green light with a wavelength of 532nm will be reflected by four sides The mirror reaches the film deposition chamber. The invention overcomes the shortcomings of the prior art and provides a dual optical path device with simple structure and low cost. The device can integrate a laser with multiple different experimental terminals, which greatly improves the efficiency of experimental research and social production.

Description

A dual optical path device connecting a pulsed laser and a terminal experimental cavity

technical field

The invention belongs to the field of semiconductor science and technology, and in particular relates to a dual optical path device capable of effectively connecting a pulsed laser with various terminal experimental cavities (such as a thin film deposition system and a vacuum glove box).

Background technique

Lasers can work in continuous or pulsed modes. When the rate of light pulses is less than the cavity lifetime of the laser, it is called a pulsed laser. The laser generated by this laser has the advantages of high power, high stability, low emittance, etc., and it will release huge energy in an instant, making the metal material evaporate locally. In the semiconductor industry, pulsed lasers are often used to grow thin film materials. First, the high power of the laser is used to sputter the metal material into a plasma state, and then these plasma plumes are deposited on the substrate to form thin film materials such as semiconductors; in spectroscopy measurement On the one hand, a pulsed laser is used to excite the material to be tested to an unstable state, and then the characteristic absorption or emission lines of the material can be measured. Usually, a laser is equipped with a set of terminal equipment, but some lasers have two or more light outlets, and the efficiency of the laser is not high.

Our pulsed laser has three light outlets, two of which can emit two different wavelengths of laser light at the same time. Based on this situation, we designed a set of independent dual optical path devices for connecting a laser with a variety of different experimental terminals. In the entire optical path, dielectric film mirrors are mainly used to build the optical path. Lasers with different wavelengths and different optical paths need to use corresponding high-reflection dielectric films. The dual optical path device can enable one laser to carry out different experimental researches at the same time, and this improvement will greatly improve the use efficiency of the laser. Of course, we can also integrate the two optical paths into one optical path, and only use one experimental terminal to perform time-resolved measurements. This technology also has considerable practical space.

Therefore, for the deficiencies in the prior art. An improved experimental device, especially one that enables a laser to carry out different experimental studies independently at the same time, has become very important.

Contents of the invention

The technical problem to be solved by the present invention is: to overcome the deficiencies of the prior art and provide a dual optical path device with simple structure and low cost. The device can integrate a laser with multiple different experimental terminals, which greatly improves the efficiency of experimental research and social production.

The technical solution adopted in the present invention is: a dual optical path device connecting the pulse laser and the terminal experiment cavity, the dual optical path device is connected with the pulse laser, thin film deposition system and vacuum glove box, wherein: the model of the pulse laser is PRO-320Nd :YAG laser, the laser is produced by Nd:YAG crystal with a characteristic wavelength of 1064 nanometers. After frequency doubling, it can generate a laser with a wavelength of 532 nanometers. Two lasers with different wavelengths have different exits. The thin film deposition system is used to deposit plasma Body Yuhui, and then form thin film materials such as semiconductors. The dual optical path device is composed of seven dielectric film mirrors, a focusing mirror, corresponding mirror frames, reaction furnaces, and optical path protection equipment. The two optical paths correspond to wavelengths of 1064 nm and 532 nm respectively. Nano-laser, in which the invisible infrared light with a wavelength of 1064 nanometers reaches the reaction furnace through three dielectric film mirrors and one focusing mirror; the visible green light with a wavelength of 532 nanometers passes through four dielectric film mirrors and reaches the deposition chamber.

Further, the model of the vacuum glove box is Universal (1500/750/900), which is used for spectroscopic measurement.

Further, the pulsed laser has strong stability, low emittance, and a repetition frequency of 10 Hz.

Furthermore, lasers with different wavelengths need to use corresponding dielectric film mirrors, so as to obtain higher reflection efficiency.

Furthermore, the use of a dual optical path device can greatly improve the efficiency of laser use, and at the same time bring a lot of convenience to experimental research.

The advantage of the present invention compared with prior art is:

(1), the design cost of the present invention is lower, also comparatively easy to realize.

(2) The present invention realizes the connection between one laser and two or more sets of experimental instruments.

(3) The invention can make the laser grow and test the material independently at the same time, make up for the deficiencies of the existing equipment, and greatly improve the use efficiency of the pulse laser.

Description of drawings

Fig. 1 is a schematic block diagram of the present invention.

Fig. 2 is an assembly drawing of the overall structure of the present invention.

Figure 3 is a schematic diagram of the optical path in the system.

Detailed ways

In the following description, for purposes of explanation, certain details are set forth in order to provide a thorough understanding of the invention. It will be apparent, however, to one skilled in the art that the invention may be practiced with some or all of its features, and that the invention may be practiced without some of the specific details. In other instances, well-known structures and devices are shown in block diagram form in order not to obscure the underlying principles of the invention.

It should be understood that FIGS. 1-3 are schematic only and may not be drawn to scale.

The invention designs a dual optical path device capable of effectively connecting a laser and two experimental cavities. Below in conjunction with accompanying drawing, describe the specific embodiment of the present invention in detail:

Fig. 1 is a functional block diagram of the present invention. Usually, the laser light generated by the pulsed laser 11 will go through the optical path to the experimental terminal such as the thin film deposition system 13 or the vacuum glove box 14 . But our laser has three light outlets, and can generate laser light of at least two wavelengths at the same time. The current optical system only connects a pulsed laser 11 with a thin film deposition system 13, and only one light outlet of the pulsed laser can be used. The design does not make efficient use of pulsed lasers. We designed a set of dual optical path device 12 which can organically combine the pulsed laser 11 with the thin film deposition system 13 and the vacuum glove box 14 . The lasers with wavelengths of 1064nm and 532nm generated from the pulsed laser reach different terminal systems through different optical paths. We can use two lasers that do not interfere with each other to complete different experimental research, which can integrate resources well and improve the efficiency of experimental research.

Fig. 2 is an assembly drawing of the overall structure of the present invention. The left part of Figure 2 is the laser part of the whole system, the middle part of Figure 2 is the vacuum glove box part of the whole system, and the right part of Figure 2 is the thin film deposition part of the whole system, we just drew a schematic diagram of this part. The pulse laser 11 is placed horizontally on the laser platform 21 to ensure that the generated laser is along the horizontal direction. The laser model we use is PRO-320Nd:YAG. The laser produced by this laser has strong stability and small emittance (the light spot at the light exit The size is 8-10 mm), and the repetition rate is 10 Hz. In this laser, the initial wavelength of 1064nm characteristic laser emitted by Nd:YAG passes through the oscillator and amplifier, and before reaching the exit, it will pass through the frequency doubling crystal to produce frequency doubling effect, which can simultaneously generate wavelengths of 532nm, 355nm, 266nm For nanometer lasers, we mainly use 1064nm and 532nm lasers for experimental research. The lasers of these two wavelengths will pass through different light outlets. Our measurement results show that the laser powers with wavelengths of 1064 nanometers and 532 nanometers are 5.6 watts and 2.7 watts respectively. The former is invisible infrared light and the latter is green light. The laser light that is produced by laser 11 can pass through light path protection box one 22, arrives light path protection box two 24 (box two 24 is supported by support 23), two beams of laser light continue to reach protection box three 25 by box two 24 mirror reflections. Wherein the laser with a wavelength of 1064 nanometers will enter the interior of the vacuum glove box 14 vertically through the reflector, and then reach the measurement position through focusing; The two optical paths do not interfere with each other. The 1064nm laser is mainly used for the laser-induced breakdown spectroscopy (LIBS) analysis of high-temperature molten salts in a vacuum glove box, that is, the use of high-energy pulsed lasers to analyze molten chloride salts and transition metal ions in high-temperature heating. Laser focused ablation or sputtering with rare earth metal ions. Therefore, in order to maintain the harsh conditions of molten chlorine salt anhydrous and oxygen-free, we fill the glove box with protective gas, such as nitrogen, argon or helium, and maintain negative pressure when synthesizing samples in the glove box, and when the sample is subjected to laser ablation Need to maintain positive pressure. In our research, we found that the optical path will be greatly affected by the air pressure, especially under positive and negative pressures, there will be a large difference in the optical path, so we adopt the design of the vertical incidence of the optical path. This optical path will not be greatly affected by the air pressure. For us Experimental research is of great help. The main research method inside the glove box is to use the laser to sputter the molten chlorine salt into plasma, and at the same time, use the optical fiber to couple the spectral signal emitted by the plasma to the spectrometer, so as to make a spectroscopic analysis of the components and contents of the molten salt. Prepare. Another 532nm laser beam will reach the thin film deposition system 13, which is built by us by purchasing parts from the United States. In the thin film deposition system 13, the 532nm laser can sputter different metal evaporation sources and sputter them into a plasma state. Finally, these plasma plumes are deposited on the substrate to form a thin film. The properties of the thin film are mainly affected by the evaporation source and the evaporation process. Impact.

Fig. 3 is a schematic diagram of the optical path in the present invention. The infrared laser with a wavelength of 1064 nanometers emitted by the laser 11 is emitted horizontally from the exit 31 through the first reflector 32, then rises vertically to the reflector 33, then descends vertically through the reflector 34, passes through the focusing mirror 35, and finally arrives in the vacuum glove box for reaction Furnace 36; the second beam of 532nm green light emitted by the laser 11 is sent horizontally from the exit 37 (the distance between the two exits 31, 37 is about 10 cm), passes through the reflectors 38, 39, 310, 311 respectively, and finally reaches the film The deposition chamber 312 inside the deposition system 13 . At present, the efficiency of ordinary reflectors is about 90%. After three or four reflectors, the laser intensity will be attenuated more, so we use mirrors coated with dielectric films as reflectors. This kind of mirrors has very high reflection efficiency, which can It is ensured that the intensity of the laser light reaching the reaction furnace 36 and the deposition chamber 312 will not drop much. When using this kind of mirror, it is necessary to make corresponding dielectric films for lasers with different wavelengths and different incident and outgoing angles.

The design of the dual optical path system is relatively simple and portable, which can effectively improve the efficiency of experimental research. According to the above design, the components required to complete the design of the dual optical path system are shown in Table 1 for details.

Table 1 Parts required for independent cavity

name quantity model pulsed laser 1 PRO-320 Vacuum Glove Box 1 Universal (1500/750/900) Thin Film Deposition System 1 Procurement of parts, self-installation Dielectric film mirror 4 532 nm Dielectric film mirror 3 1064 nm focusing lens 1

In a word, the present invention realizes the natural connection between one laser and multiple sets of experimental instruments. The system has a simple structure and is convenient to build. After being put into use, resources can be well integrated and the use efficiency of instruments and equipment can be improved.

The parts not described in detail in the present invention belong to the known technology in the art.

Although the illustrative specific embodiments of the present invention have been described above, so that those skilled in the art can understand the present invention, it should be clear that the present invention is not limited to the scope of the specific embodiments. For those of ordinary skill in the art, as long as Various changes are within the spirit and scope of the present invention defined and determined by the appended claims, and these changes are obvious and should be included within the scope of the claims of the present invention.

Claims (5)

1. A dual optical path device connecting a pulsed laser and a terminal experiment cavity, characterized in that: the dual optical path device (12) is effectively connected to a pulsed laser (11), a thin film deposition system (13) and a vacuum glove box (14), Wherein: the model of pulse laser (11) is PRO-320 Nd:YAG, and this laser produces the characteristic wavelength of 1064 nanometer wavelengths by Nd:YAG crystal, can produce the laser that wavelength is 532 nanometers through frequency doubling, the laser of two different wavelengths There are different outlets respectively. The thin film deposition system (13) is used to deposit plasma plumes, and then form thin film materials such as semiconductors. The dual optical path device (12) consists of seven dielectric film mirrors, one focusing mirror and corresponding mirror frames. , reaction furnace (36) and light path protection equipment, two light paths correspond to the laser light with a wavelength of 1064 nanometers and 532 nanometers respectively, wherein the invisible infrared light with a wavelength of 1064 nanometers passes through three dielectric film reflectors (32, 33, 34 ) and a focusing mirror (35) reach the reaction furnace (36); the visible wavelength of 532 nm green light will reach the deposition chamber (312) after passing through the four dielectric film mirrors (38, 39, 310, 311). 2. A kind of dual optical path device connecting the pulsed laser and the terminal experiment cavity according to claim 1, characterized in that: the model of the vacuum glove box (14) is Universal (1500/750/900), which is used for spectroscopy Measurement. 3. A dual optical path device connecting the pulsed laser and the terminal experiment cavity according to claim 1, characterized in that: the pulsed laser (11) has strong stability, low emittance, and a repetition rate of 10 Hz. 4. A dual optical path device connecting the pulsed laser and the terminal experiment cavity according to claim 1, characterized in that: lasers with different wavelengths need to use corresponding dielectric film mirrors, so that higher reflection efficiency can be obtained. 5. A dual optical path device connecting the pulsed laser and the terminal experimental cavity according to claim 1, characterized in that: the use of the dual optical path device can greatly improve the efficiency of the laser, and also bring a lot of benefits to the experimental research. convenient.