DBD oxygen plasma method for rapidly sensitizing semiconductor film at room temperature and application

Abstract

The invention provides a DBD oxygen plasma method for rapidly sensitizing a semiconductor film at room temperature and application, and belongs to the technical field of material treatment processes. According to the method, the lead selenide thin film is treated by combining specific DBD oxygen plasma conditions, the sensitized semiconductor thin film is successfully prepared, rapid sensitization at the room temperature is achieved, and the problems that an existing PbSe and other IV-VI group compound semiconductor thin film sensitization technology is complex in equipment, tedious in process, high in temperature, long in consumed time and the like are solved. According to the processing method provided by the invention, the grain size of the semiconductor film can be changed, meanwhile, the content of lead oxides in the film is adjusted, the prepared film is smooth in surface and uniform in particle, no obvious defect is observed on the surface, and an infrared detector prepared based on the film is excellent in photoelectric response capability.

Description

Technical Field

[0001] The invention relates to the technical field of material processing technology, and in particular to a DBD oxygen plasma sensitization method for rapidly sensitizing a semiconductor film at room temperature and its application. Background Art

[0002] As the foundation of modern science and technology, semiconductor materials are widely used in integrated circuits, communication systems, energy conversion, photoelectric detection and other fields due to their unique physical properties. With the continuous development of science and technology, semiconductor materials further promote innovation and progress in various industries and provide important support for building an information-based and intelligent society.

[0003] Lead selenide (PbSe) is a typical IV-VI compound semiconductor material with a rock salt structure, with a band gap of 0.27 eV at room temperature and an exciton Bohr radius of 46 nm. It has attracted widespread attention in the field of photodetectors due to its advantages such as high sensitivity, good thermal stability and low manufacturing cost in the near-mid-infrared spectral range.

[0004] Studies have shown that there are a variety of physical and chemical methods to prepare PbSe thin films. However, no matter which method is used to prepare the initial PbSe film, it is insensitive to infrared light and cannot convert infrared light into an electrical signal that can be recorded. Therefore, it needs to be sensitized. At present, the sensitization method is mainly thermal oxidation treatment, which is to heat treat the PbSe film in an oxygen atmosphere. This process can effectively activate the infrared light response ability of PbSe. However, thermal oxidation sensitization treatment needs to be carried out at high temperature (400°C or higher) for more than 30 minutes, which has the disadvantages of low efficiency and complex experimental conditions.

[0005] Chinese patent CN116904936A discloses a PbSe infrared detection film, a preparation method thereof, and an infrared detector. The preparation method of the PbSe infrared detection film comprises: adding an oxidizing element into a target material by pre-sensitization to obtain a physical vapor deposition target material, and adopting an electron beam evaporation method to deposit and prepare a sensitized PbSe film, thereby avoiding element segregation caused by a high temperature process, and also overcoming the defect that the film cannot be deposited on a substrate such as a flexible organic material due to high temperature limitations, and facilitating compatibility with modern electronic manufacturing technology.

[0006] However, the photoelectric response capability of PbSe thin film products in the existing technology needs to be further improved. Summary of the invention

[0007] The purpose of the present invention is to provide a DBD oxygen plasma method and application for rapid sensitization of semiconductor films at room temperature, to achieve rapid sensitization treatment of IV-VI group compound semiconductor film materials, to make them have excellent photoelectric response capabilities, and to solve the problems of complex equipment, cumbersome processes, high temperature requirements, and long time consumption in existing sensitization technologies.

[0008] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0009] The present invention provides a method for preparing a DBD oxygen plasma sensitized semiconductor film, comprising the following steps:

[0010] The lead selenide film is treated with DBD oxygen plasma to obtain a DBD oxygen plasma sensitized semiconductor film;

[0011] The power of the DBD oxygen plasma treatment is 40 to 60 W;

[0012] The DBD oxygen plasma treatment time is 60 to 120 seconds.

[0013] Preferably, the electrode gap in the DBD oxygen plasma treatment is 6 to 10 mm.

[0014] Preferably, the medium used in the DBD oxygen plasma treatment is a quartz glass sheet.

[0015] Preferably, the lead selenide thin film is prepared by magnetron sputtering.

[0016] Preferably, the magnetron sputtering method comprises the following steps:

[0017] Place the substrate in the chamber of the magnetron sputtering equipment and set the vacuum degree to 5×10 -4 ~10 -3 Pa, substrate temperature is 160-200°C;

[0018] Working gas is introduced, and magnetron sputtering is performed using a lead selenide target to obtain a lead selenide film.

[0019] Preferably, the substrate is an ITO glass substrate.

[0020] Preferably, the working gas is argon;

[0021] and / or, the volume flow rate of the working gas is 20 to 40 sccm;

[0022] And / or, after the working gas is introduced, the pressure of the chamber of the magnetron sputtering equipment is 0.5-1.5Pa.

[0023] Preferably, the power of the magnetron sputtering is 60 to 100 W;

[0024] The magnetron sputtering time is 80 to 100 minutes.

[0025] The invention also provides a DBD oxygen plasma sensitized semiconductor film prepared by the preparation method.

[0026] The present invention also provides application of the DBD oxygen plasma sensitized semiconductor film in a photoelectric detector.

[0027] Beneficial effects of the present invention:

[0028] The present invention combines specific DBD oxygen plasma conditions to treat the lead selenide film, successfully prepares an oxygen-sensitized semiconductor film, and realizes rapid sensitization at room temperature. After testing, it is known that the preparation method provided by the present invention can change the grain size of the semiconductor film, and at the same time adjust the content of lead oxide compounds in the film, and the surface of the prepared film is flat, the particles are uniform, and no obvious defects are observed on the surface. The infrared detection device prepared based on this film has excellent photoelectric response ability. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic diagram of a DBD oxygen plasma generator device;

[0030] Figure 2 The surface SEM image of DBD oxygen plasma sensitized PbSe semiconductor film;

[0031] Figure 3 This is the XRD diffraction pattern of DBD oxygen plasma sensitized PbSe semiconductor film;

[0032] Figure 4 It is a point-line graph of grain size data;

[0033] Figure 5 This is the XPS spectrum of DBD oxygen plasma sensitized PbSe semiconductor film, where: Figure 5 a is the full spectrum of DBD oxygen plasma sensitized PbSe semiconductor film; Figure 5 b is Se 3d narrow spectrum; Figure 5 c is the narrow spectrum of Pb 4f; Figure 5 d is the O1s narrow spectrum;

[0034] Figure 6 is the voltage-current (IV) curve, where: Figure 6 a is an IV curve of the detection device made of PbSe semiconductor thin film obtained in Comparative Example 1 (DBD oxygen plasma parameters: 0 W, 0 s, i.e., untreated); Figure 6b is the IV curve of the detection device made of DBD oxygen plasma sensitized PbSe semiconductor thin film obtained in Example 1 (DBD oxygen plasma parameters: 45W, 120s); Figure 6 c is an IV curve of the detection device made of DBD oxygen plasma sensitized PbSe semiconductor thin film obtained in Example 2 (DBD oxygen plasma parameters: 60W, 60s); Figure 6 a is an IV curve of the detection device made of DBD oxygen plasma sensitized PbSe semiconductor thin film obtained in Example 3 (DBD oxygen plasma parameters: 60W, 120s);

[0035] Figure 7 Statistical bar chart of the responsivity and specific detectivity of thin film optoelectronic devices. DETAILED DESCRIPTION

[0036] The technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0037] The DBD oxygen plasma generator used in the embodiments of the present invention is of model CTP-2000K, and is manufactured by Nanjing Suman Plasma Technology Co., Ltd.

[0038] Example 1

[0039] The present invention provides a DBD oxygen plasma method for rapidly sensitizing a semiconductor film at room temperature, the preparation method comprising the following steps:

[0040] (1) The ITO glass substrate was ultrasonically cleaned with deionized water and alcohol for 10 min respectively, and then dried with nitrogen to obtain a substrate with a clean surface.

[0041] (2) The substrate was transferred to the chamber of the magnetron sputtering equipment, and the distance from the PbSe target was kept at 50 mm. The vacuum degree in the chamber was adjusted to 8.0×10 -4 Pa, and heat the substrate to 180°C.

[0042] (3) Argon gas with a flow rate of 30 sccm was introduced into the chamber, and the pressure in the chamber was adjusted to 1.0 Pa. Before sputtering, the substrate was shielded with a baffle, the rotation speed was adjusted to 12 r / min, and pre-sputtering was performed for 6 minutes to ensure that the pressure and power were stable.

[0043] (4) Adjust the RF power of the lead selenide target to 80 W, observe ignition in the chamber, and then sputter for 90 minutes.

[0044] (5) After the sputtering is completed, the lead selenide film is placed in a DBD oxygen plasma reactor. The electrode gap is adjusted to 8 mm, and quartz glass sheets are placed above and below as a medium.

[0045] (6) Adjust the frequency knob to find the maximum operating current and adjust it to 85% of the maximum current. Preheat for 1 minute and wait for the current and voltage to stabilize.

[0046] (7) The power of the DBD oxygen plasma generator was adjusted to 45 W, and the film sample was treated in an air environment for 120 s, thereby finally obtaining the DBD oxygen plasma fast sensitized semiconductor film at room temperature.

[0047] The DBD oxygen plasma generator device in the embodiment is as follows Figure 1 shown.

[0048] The DBD oxygen plasma fast sensitized semiconductor film at room temperature is made into an infrared photodetector, and the specific steps are as follows:

[0049] The mask is placed on the sensitized film and fixed in the chamber of the thermal evaporation equipment.

[0050] Place 5 g of aluminum sheet into the evaporation boat and use a high-speed molecular pump to adjust the air pressure in the chamber to below 3.5×10-3Pa.

[0051] Check whether the electrodes inside the chamber are in contact, select manual adjustment, and adjust the power to 300W.

[0052] The thermal evaporation was performed for 30 minutes, and the sample was taken out after cooling to room temperature. After the mask was removed, the DBD oxygen plasma fast sensitization semiconductor film at room temperature was obtained to be made into an infrared photodetector.

[0053] Example 2

[0054] The present invention provides a DBD oxygen plasma method for rapidly sensitizing a semiconductor film at room temperature, the preparation method comprising the following steps:

[0055] (1) The ITO glass substrate was ultrasonically cleaned with deionized water and alcohol for 12 min respectively, and then dried with nitrogen to obtain a substrate with a clean surface.

[0056] (2) The substrate was transferred to the chamber of the magnetron sputtering equipment, and the distance from the PbSe target was kept at 60 mm. The vacuum degree in the chamber was adjusted to 7×10 -4 Pa, and heat the substrate to 180°C.

[0057] (3) Argon gas at a flow rate of 30 sccm was introduced into the chamber, and the pressure in the chamber was adjusted to 1.0 Pa. Before sputtering, the substrate was shielded with a baffle, the rotation speed was adjusted to 14 r / min, and pre-sputtering was performed for 7 minutes to ensure that the pressure and power were stable.

[0058] (4) Adjust the RF power of the lead selenide target to 80 W, observe ignition in the chamber, and then sputter for 90 minutes.

[0059] (5) After the sputtering is completed, the lead selenide film is placed in a DBD oxygen plasma reactor. The electrode gap is adjusted to 8 mm, and quartz glass sheets are placed above and below as a medium.

[0060] (6) Adjust the frequency knob to find the maximum operating current and adjust it to 85% of the maximum current. Preheat for 2 minutes until the current and voltage are stable.

[0061] (7) The power of the DBD oxygen plasma generator was adjusted to 60 W, and the treatment was performed in an air environment for 60 seconds, thereby finally obtaining the DBD oxygen plasma fast sensitized semiconductor film at room temperature.

[0062] Example 3

[0063] The present invention provides a DBD oxygen plasma method for rapidly sensitizing a semiconductor film at room temperature, the preparation method comprising the following steps:

[0064] (1) The ITO glass substrate was ultrasonically cleaned with deionized water and alcohol for 14 min respectively, and then dried with nitrogen to obtain a substrate with a clean surface.

[0065] (2) The substrate was transferred to the chamber of the magnetron sputtering equipment, keeping a distance of 70 mm from the PbSe target. The vacuum degree in the chamber was adjusted to 7.5×10 -4 Pa, and heat the substrate to 180°C.

[0066] (3) Argon gas with a flow rate of 30 sccm was introduced into the chamber, and the pressure in the chamber was adjusted to 1.0 Pa. Before sputtering, the substrate was shielded with a baffle, the rotation speed was adjusted to 15 r / min, and pre-sputtering was performed for 8 minutes to ensure that the pressure and power were stable.

[0067] (4) Adjust the RF power of the lead selenide target to 80 W, observe ignition in the chamber, and then sputter for 90 minutes.

[0068] (5) After the sputtering is completed, the lead selenide film is placed in a DBD oxygen plasma reactor. The electrode gap is adjusted to 8 mm, and quartz glass sheets are placed above and below as a medium.

[0069] (6) Adjust the frequency knob to find the maximum operating current and adjust it to 85% of the maximum current. Preheat for 3 minutes until the current and voltage are stable.

[0070] (7) The power of the DBD oxygen plasma generator is adjusted to 60 W, and the treatment is carried out in an air environment for 120 seconds to finally obtain the DBD oxygen plasma fast sensitized semiconductor film at room temperature.

[0071] Comparative Example 1

[0072] This comparative example provides a DBD oxygen plasma method for rapidly sensitizing a semiconductor film at room temperature. Compared with Example 1, the difference is that in step (7), the power of the DBD oxygen plasma generator is adjusted to 0 W, and the PbSe film is treated for 0 s in an air environment. Other operations are the same.

[0073] Comparative Example 2

[0074] This comparative example provides a DBD oxygen plasma method for rapidly sensitizing a semiconductor film at room temperature. Compared with Example 1, the difference is that in step (7), the power of the DBD oxygen plasma generator is adjusted to 60 W, and the PbSe film is treated for 180 s in an air environment. Other operations are the same.

[0075] Comparative Example 3

[0076] This comparative example provides a DBD oxygen plasma method for rapidly sensitizing a semiconductor film at room temperature. Compared with Example 1, the difference is that in step (7), the power of the DBD oxygen plasma generator is adjusted to 80 W, and the PbSe film is treated for 120 s in an air environment. Other operations are the same.

[0077] Experimental example

[0078] The DBD oxygen plasma rapid sensitization semiconductor films obtained in Example 1, Example 2, Example 3, Comparative Example 1, Comparative Example 2, and Comparative Example 3 at room temperature were tested.

[0079] (I) SEM test and particle size distribution

[0080] The surface of the PbSe semiconductor film after DBD oxygen plasma treatment was detected using a scanning electron microscope (SEM). The results of the SEM photos are as follows: Figure 2 As shown. Figure 2 It can be seen that the films are uniform after the initial PbSe is treated with DBD oxygen plasma with different parameters, and the crystal size shows an increasing trend with the increase of treatment time and power. At the same time, it is noted that with the increase of power and the extension of treatment time, obvious defects appear on the surface of comparative examples 2 and 3, so there is no need to detect them again in subsequent tests.

[0081] (ii) XRD test and grain size

[0082] The PbSe semiconductor film after DBD oxygen plasma treatment was tested by X-ray diffractometer. The results of XRD diffraction spectrum are as follows: Figure 3 As shown. Figure 3It can be seen that after DBD oxygen plasma treatment of each group, the semiconductor film still corresponds well to the PbSe standard peak. However, the characteristic peak intensity has obvious changes: with the change of DBD treatment power and time, the types of lead oxide compounds increase (such as PbO, PbO2, PbSeO4, Pb2SeO5), and the diffraction peak intensity gradually increases, indicating that when the PbSe film is treated with 60W DBD oxygen plasma for 120s, an appropriate amount of active oxygen can be introduced into the film.

[0083] After statistics of particle sizes of different groups, the results are as follows Figure 4 As shown by Figure 4 It can be seen that when the DBD oxygen plasma parameters are 60 W and 120 s, the grain size is relatively larger.

[0084] (III) XPS test

[0085] X-ray photoelectron spectroscopy was used to detect the PbSe semiconductor film after DBD oxygen plasma treatment. The results of XPS spectrum are as follows: Figure 5 As shown. Figure 5 It can be seen that Pb, Se, O and C elements are detected in the spectrum, indicating that DBD oxygen plasma does not introduce any other impurities during the treatment of the film. From the narrow spectrum scanning results, it can be observed that the content of oxides has obvious changes. Under different oxygen plasma conditions, the lead-selenium atomic ratios of Comparative Example 1, Example 1, Example 2, and Example 3 are 1.55, 1.53, 1.56, and 1.49, respectively, indicating that DBD oxygen plasma treatment can adjust the lead-selenium atomic ratio.

[0086] 4) Photoelectric performance test

[0087] The photoelectric performance of the PbSe semiconductor thin film infrared photodetector after DBD oxygen plasma treatment was tested using a semiconductor tester. The IV curve results are shown in the figure below. Figure 6 As shown. Figure 6 It can be seen that the infrared detectors made of films treated with DBD oxygen plasma with different parameters have light-to-dark current ratios of 1.12, 1.61, 1.42 and 2.32 at a working voltage of -6V. The infrared detector made of films treated with DBD oxygen plasma at 60W for 120s has a significantly improved light-to-dark current ratio. Figure 7 As shown. Figure 7 It can be seen that when the DBD oxygen plasma parameters are 60W and 120s, the responsivity and specific detectivity reach the peak values ​​of 734.8mA / W and 6.36×10 9 Jones, indicating that the thin-film infrared photodetector at this time has better performance.

[0088] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for preparing a DBD oxygen plasma sensitized semiconductor film, characterized in that: The following steps are involved: The lead selenide film is subjected to DBD oxygen plasma treatment to obtain a DBD oxygen plasma sensitized semiconductor film; The power of the DBD oxygen plasma treatment is 40 to 60 W; The DBD oxygen plasma treatment time is 60 to 120 seconds.

2. The preparation method according to claim 1, characterized in that: The electrode gap during DBD oxygen plasma treatment is 6 to 10 mm.

3. The preparation method according to claim 1, characterized in that: The medium used in the DBD oxygen plasma treatment is a quartz glass sheet.

4. The preparation method according to any one of claims 1 to 3, characterized in that: The lead selenide film is prepared by magnetron sputtering.

5. The preparation method according to claim 4, characterized in that: The magnetron sputtering method comprises the following steps: Place the substrate in the chamber of the magnetron sputtering equipment and set the vacuum degree to 5×10 -4 ~10 -3 Pa, substrate temperature is 160-200°C; Working gas is introduced, and magnetron sputtering is performed using a lead selenide target to obtain a lead selenide film.

6. The preparation method according to claim 5, characterized in that: The substrate is an ITO glass substrate.

7. The preparation method according to claim 5, characterized in that: The working gas is argon; and / or, the volume flow rate of the working gas is 20 to 40 sccm; And / or, after the working gas is introduced, the pressure of the chamber of the magnetron sputtering equipment is 0.5-1.5Pa.

8. The preparation method according to claim 5, characterized in that: The power of the magnetron sputtering is 60 to 100 W; The magnetron sputtering time is 80 to 100 minutes.

9. A DBD oxygen plasma sensitized semiconductor thin film prepared by the preparation method according to any one of claims 1 to 8.

10. Use of the DBD oxygen plasma sensitized semiconductor film according to claim 9 in the preparation of photodetectors.

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