CN114645321B - Co 9 S 8 Method for preparing single crystal transition metal sulfide film - Google Patents

Abstract

The invention belongs to the field of pulsed laser deposition technology and preparation of transition metal sulfide films, and specifically provides a method for preparing Co ₉ S ₈ single crystal transition metal sulfide films, so as to obtain high-quality epitaxial sulfide films. The present invention utilizes the pulsed laser deposition method to prepare Co ₉ S ₈ single crystal epitaxial film for the first time through the preparation of CoS target and precise design of deposition parameters. Compared with Co ₉ S ₈ powder or bulk, Co ₉ S ₈ single crystal The epitaxial film can have better physical properties. Compared with the existing transition metal sulfide film, the Co ₉ S ₈ single crystal epitaxial film has the advantages of high crystal quality, thinner thickness, and good electrical transport performance; in summary, this paper The invention is based on the pulsed laser deposition method to prepare the Co ₉ S ₈ single crystal epitaxial film for the first time, which has the advantages of high quality, thin thickness and good electrical transport performance, which provides a good foundation for its application in the energy field, and the preparation process Simple and low preparation cost.

Description

A kind of preparation method of Co9S8 single crystal transition metal sulfide film

technical field

The invention belongs to the field of pulse laser deposition technology and the preparation of transition metal sulfide thin films, and specifically provides a preparation method of Co ₉ S ₈ single crystal transition metal sulfide thin films.

Background technique

Transition metal sulfide thin films play a very important role in the fields of optoelectronic devices, photovoltaic cells, thermoelectric devices, sensors, etc. At present, most transition metal sulfide thin films prepared are rough and have high-density defects, and the film thickness is often dozens of Micron, limited performance and high density of defects make people more research direction to high-quality single crystal and extremely thin epitaxial film. However, due to the mismatch of lattice parameters and thermal expansion, it is very difficult to directly deposit sulfide epitaxial films on oxide substrates by one-step method; at the same time, traditional top-down techniques cannot achieve Nanoscale precision control; therefore, obtaining high-quality epitaxial sulfide films on larger substrates remains a considerable challenge.

Contents of the invention

The purpose of the present invention is to provide a method for preparing a Co ₉ S ₈ single crystal transition metal sulfide thin film. The Co ₉ S ₈ single crystal epitaxial thin film is prepared for the first time, and has excellent electrical properties and good stability. A series of excellent properties of Co ₉ S ₈ provide samples.

To achieve the above object, the technical solution adopted in the present invention is:

A method for preparing a Co ₉ S ₈ single crystal transition metal sulfide film, comprising the steps of:

Step 1. Grinding, tableting, and high-temperature calcination with CoS powder as the reaction material to obtain the CoS target;

Step 2. Use acetone, alcohol, and deionized water to ultrasonically clean the YSZ substrate in sequence, and dry it with nitrogen for later use;

Step 3. Place the CoS target and the YSZ substrate in the sputtering chamber of the pulsed laser deposition system, set the distance between the target and the substrate to be 55 mm, and set the background vacuum of the pulsed laser deposition system to 4.5×10 ^-4 Pa , The growth temperature is 500°C-600°C, the pulse laser repetition frequency is set to 9Hz, the pulse laser energy density is 1.6J/cm ² , the deposition pulse number is 18000pulses-30000pulses, and the pulsed laser deposition system is used to deposit and grow on the YSZ substrate. Co ₉ S ₈ single crystal transition metal sulfide films.

Further, in the step 1, the CoS powder is used in an amount of 1g-2g.

Further, in the step 1, the grinding is carried out in a vacuum glove box, and the grinding time is 25min-30min.

Further, in the step 1, tablet pressing is carried out with a tablet pressing machine, the setting pressure is 15Mpa-20Mpa, and the tablet pressing time is 8min-10min. After the tablet pressing is completed, it is transferred to the quartz tube together with the ceramic gasket, and then Vacuum seal the tubes using a vacuum tube sealer.

Further, in the step 1, the high-temperature calcination is carried out using a tube furnace. First, a corundum tube is placed in the tube furnace, and then a quartz tube equipped with a target is placed in the corundum tube to prevent the volatilization of sulfide from causing The quartz tube burst, and the parameters for high-temperature calcination are: heating from room temperature to 750°C at a heating rate of 5°C/min, and holding for 10h-12h.

Further, in the step 3, the CoS target material is ground with sandpaper and glued to the target holder with conductive carbon, and the YSZ substrate is glued to the substrate table with conductive silver paste.

Further, the thickness of the Co ₉ S ₈ single crystal transition metal sulfide film is 60nm-100nm.

The beneficial effects of the present invention are:

The present invention provides a method for preparing a Co ₉ S ₈ single crystal transition metal sulfide thin film. The pulsed laser deposition method is used to prepare a Co ₉ S ₈ single crystal epitaxial thin film for the first time through the preparation of a CoS target and the precise design of deposition parameters. Compared with Co ₉ S ₈ powder or bulk, Co ₉ S ₈ single crystal epitaxial film can have better physical properties. Compared with existing transition metal sulfide films, Co ₉ S ₈ single crystal epitaxial film has crystalline quality High, thin thickness, and good electrical transport properties; in summary, the present invention is the first to prepare Co ₉ S ₈ single crystal epitaxial film based on pulsed laser deposition, which has the advantages of high quality, thin thickness, and good electrical transport properties , providing a good foundation for its application in the energy field, and the preparation process is simple and the preparation cost is low.

Description of drawings

Fig. 1 is the XRD pattern measured for the calibrated YSZ (002) orientation of Co ₉ S ₈ single crystal thin films prepared in Examples 1, 2, and 3 of the present invention.

Fig. 2 is an RSM diagram measured for the calibrated YSZ (002) orientation of the Co ₉ S ₈ single crystal thin film prepared in Example 1 of the present invention.

Fig. 3 is a Phi-Scan diagram measured by the calibration YSZ (202) of the Co ₉ S ₈ single crystal thin film prepared in Example 1 of the present invention.

Fig. 4 is a temperature-varying resistance diagram of Co ₉ S ₈ single crystal thin films prepared in Examples 1, 2, and 3 of the present invention.

Detailed ways

The present invention will be described in further detail below in conjunction with the accompanying drawings and embodiments.

Example 1

This embodiment provides a method for preparing a Co ₉ S ₈ single crystal transition metal sulfide film, which specifically includes the following steps:

Step 1. Weigh 2g of CoS powder, and grind it in a vacuum glove box for 30 minutes with an agate mortar; after grinding, use a tablet machine to compress the tablet, the tablet pressure is 20Mpa, and the time is 10min; The target material and the ceramic spacer were put into the quartz tube together, and the tube was vacuum sealed with a vacuum tube sealing machine, and the vacuum degree of the tube sealing was controlled at 4.5×10 ^-4 Pa; after the tube sealing was completed, the quartz tube was put into the tube furnace Carry out target sintering, the sintering temperature is 750°C, the holding time is 12h, and the heating rate is 5°C/min. After the sintering is completed, the CoS target can be obtained;

Step 2. Use acetone, alcohol, and deionized water to ultrasonically clean the YSZ substrate in sequence, and the cleaning time is 5 minutes each; after cleaning, use a nitrogen gun to dry it;

Step 3. First use fine sandpaper to polish the sintered target, and then use conductive carbon glue to stick the target to the target holder; use conductive silver paste to stick the YSZ substrate to the substrate table , and quickly dry the silver paste with a heating platform; put the target and the substrate together into the pulsed laser deposition system, and the distance between the target and the substrate is controlled at 55mm; deposit and grow on the YSZ substrate in the pulsed laser deposition system Co ₉ S ₈ single crystal transition metal sulfide film, deposition and growth parameters are: vacuum controlled at 4.5×10 ^-4 Pa, temperature at 600°C, laser frequency at 9Hz, energy density at 1.6J/cm ² , laser pulse number 18000 pulses, a Co ₉ S ₈ single crystal transition metal sulfide film with a thickness of 60 nm can be obtained.

Example 2

This embodiment provides a method for preparing a Co ₉ S ₈ single crystal transition metal sulfide film. The only difference between it and Embodiment 1 is that in step 3, the number of laser pulses is changed from 18000 pulses to 30000 pulses, and the obtained thickness is changed from 60 nm to 30000 pulses. 100 nm _Co9S8 single _- crystal transition metal sulfide films.

Example 3

This example provides a method for preparing a Co ₉ S ₈ single crystal transition metal sulfide film. The only difference between it and Example 1 is that in Step 3, the growth temperature is changed from 600°C to 700°C, and other growth conditions Unchanged _Co9S8 single _- crystal transition metal sulfide films.

As shown in Figure 1, the XRD pattern measured for the calibration (002) orientation of the Co ₉ S ₈ thin film prepared in the above-mentioned embodiments 1, 2, and 3 can be seen from the figure, and the peaks that appear in the thin film are all consistent with the orientation of the substrate peak, indicating that our film is epitaxially grown.

Figure 2 shows the RSM diagram measured for the calibrated YSZ(002) orientation of the Co ₉ S ₈ film prepared in Example 1. It can be seen from the RSM diagram that the epitaxial relationship between the film and the substrate is good.

As shown in Figure 3, it is the Phi-Scan figure that the calibration YSZ (202) orientation of the Co ₉ S ₈ film prepared in Example 1 measures, as can be seen from the figure, there are 4 peaks in the film in the range of 0-360 degrees, indicating that The film has four-fold symmetry, which reflects the good epitaxial relationship between the film and the substrate.

As shown in Figure 4, it is the variable temperature resistance data diagram of the Co ₉ S ₈ film prepared in Examples 1, 2, and 3. According to the data, the resistance of Co ₉ S ₈ is very small, and the sample resistance of this test is all at 10 ohms In the following, it is known from the variation trend of resistance temperature resistance with temperature that Co ₉ S ₈ thin film resistors exhibit metallic characteristics as the temperature resistance increases, and higher temperatures and thicker films have more excellent electrical properties.

The above is only a specific embodiment of the present invention. Any feature disclosed in this specification, unless specifically stated, can be replaced by other equivalent or alternative features with similar purposes; all the disclosed features, or All method or process steps may be combined in any way, except for mutually exclusive features and/or steps.

Claims (7)

1. a Co ₉ S ₈ preparation method of single crystal transition metal sulfide film, comprising the steps: Step 1. Grinding, tableting, and high-temperature calcination with CoS powder as the reaction material to obtain the CoS target; Step 2. Use acetone, alcohol, and deionized water to ultrasonically clean the YSZ substrate in sequence, and dry it with nitrogen for later use; Step 3. Place the CoS target and the YSZ substrate in the sputtering chamber of the pulsed laser deposition system, set the distance between the target and the substrate to be 55 mm, and set the background vacuum of the pulsed laser deposition system to 4.5×10 ^-4 Pa , The growth temperature is 500°C-600°C, the pulse laser repetition frequency is set to 9Hz, the pulse laser energy density is 1.6J/cm ² , the deposition pulse number is 18000pulses-30000pulses, and the pulsed laser deposition system is used to deposit and grow on the YSZ substrate. Co ₉ S ₈ single crystal transition metal sulfide films. 2. The method for preparing the Co ₉ S ₈ single crystal transition metal sulfide film according to claim 1, characterized in that, in the step 1, the CoS powder is used in an amount of 1 g to 2 g. 3. The method for preparing the Co ₉ S ₈ single crystal transition metal sulfide film according to claim 1, characterized in that, in the step 1, the grinding is carried out in a vacuum glove box, and the grinding time is 25 minutes to 30 minutes. 4. according to the preparation method of Co ₉ S ₈ single crystal transition metal sulfide film described in claim 1, it is characterized in that, in described step 1, tabletting adopts tabletting machine to carry out, setting pressure is 15Mpa～20Mpa, tabletting The time is 8 minutes to 10 minutes. After the tablet pressing is completed, it is transferred to the quartz tube together with the ceramic gasket, and then the vacuum tube sealing machine is used to vacuum seal the tube. _5. by the preparation method of described _Co9S8 single crystal transition metal sulfide film of claim 1, it is characterized in that, in described step 1, high-temperature calcining adopts tube furnace to carry out, first puts corundum in tube furnace Then put the quartz tube with the target into the corundum tube to prevent the quartz tube from bursting due to volatile sulfide. The parameters for high-temperature calcination are: heating from room temperature to 750 °C at a heating rate of 5 °C/min 10h～12h. 6. according to the preparation method of Co ₉ S ₈ single crystal transition metal sulfide thin film described in claim 1, it is characterized in that, in described step 3, CoS target material adopts sandpaper to carry out surface grinding and sticks to target holder with conductive carbon On, the YSZ substrate is glued to the substrate table with conductive silver paste. 7. The method for preparing the Co ₉ S ₈ single crystal transition metal sulfide film according to claim 1, wherein the thickness of the Co ₉ S ₈ single crystal transition metal sulfide film is 60nm-100nm.

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