CN102372500A - Method for preparing Cu diffusion doped ZnO base semiconductor by adopting laser pulse deposition method - Google Patents

Abstract

The invention relates to a method for preparing a semiconductor thin film material. The prepared materials include substrate, ZnO base layer and diffusion layer. Its diffusion layer is a diffusion layer formed by deposition of high-temperature diffusion and doping of Cu into the ZnO base layer. The thin film is prepared by pulse laser deposition method, the substrate is (100) silicon single crystal, the vacuum degree in the laser pulse cavity is 5×10 ^-4 Pa, the deposition temperature is 450°C, the laser frequency is 4Hz, the laser energy is 190kV, and the ZnO-based thin film is sputtered The time is 40 minutes, a Cu layer is added on the above basis, the deposition time is 2 minutes, and the temperature is kept for 30 minutes. The prepared Cu diffusion-doped ZnO-based thin film is naturally cooled to room temperature in the cavity to form. The present invention is superior to the previous sintered target material sputtering coating process when preparing doped ZnO-based semiconductor thin films, and is more convenient when preparing ZnO-based semiconductor thin films with different contents.

Description

Method for preparing Cu diffusion-doped ZnO-based semiconductors by laser pulse deposition

Technical field The present invention relates to a method for preparing Cu diffusion-doped ZnO-based semiconductor thin film by pulse laser deposition method, which belongs to the technical field of semiconductor materials. the

Background technology ZnO is a wide bandgap oxide semiconductor material with excellent performance. It has many advantages in the application of electronic and optoelectronic devices. It is considered to be a new generation of optoelectronic semiconductor materials. It has broad applications in optoelectronic devices and information materials. Application prospects. However, the preparation of doped ZnO-based semiconductor thin films generally adopts a sintered target sputtering coating process, which is more complicated when preparing ZnO-based semiconductor thin films with different contents. the

Summary of the invention In order to overcome the existing complex process of preparing ZnO-based semiconductor thin films with different contents, the present invention provides a method for preparing Cu diffusion-doped ZnO-based semiconductor thin films by pulsed laser deposition, which can prepare doped semiconductors more easily. the

The invention adopts a pulse laser deposition method to prepare a Cu diffusion-doped ZnO-based semiconductor thin film method, and the prepared materials include a substrate, a ZnO base layer and a diffusion layer. It is characterized in that the diffusion layer is a diffusion layer formed by deposition of high-temperature diffusion doping of Cu into the ZnO base layer. the

The present invention has Cu diffusion-doped ZnO-based semiconductor film, which is prepared by pulse laser deposition method, the substrate is (100) silicon single crystal, the vacuum degree in the laser pulse cavity is 5×10 ^-4 Pa, the deposition temperature is 450°C, and the laser frequency is 4Hz, laser energy 190kV, ZnO thin film sputtering time 40 minutes, Cu layer was added on the above basis, deposition time was 2 minutes, 450°C was kept for 30 minutes, and Cu diffusion-doped ZnO-based thin film was prepared. The thin film is naturally cooled to room temperature in the cavity to form.

The technique of preparing Cu diffusion-doped ZnO-based semiconductor thin film by pulsed laser deposition is as follows:

(1) The substrate used in this experiment is a 2-inch single-crystal Si (100) substrate, which is polished on one side. Submerge the Si sheet in acetone, clean it in an ultrasonic generator for one hour, ultrasonically clean it with anhydrous ethanol for one hour, and clean it with ion water for one hour, then take it out and place it in a constant temperature drying oven for drying. the

(2) Fix the ZnO-based target, the Cu target and the substrate on the corresponding sample holders, adjust the distance between the substrate and the target to 50mm, then tighten the valve and close the vacuum chamber. the

(3) Turn on the cooling water of the molecular pump, turn on the power, turn on the mechanical pump, open the side pumping valve, and turn on the vacuum gauge after a few minutes. When the system vacuum reaches ^2-3 Pa, close the bypass valve, open the isolation valve, and start the molecular pump.

(4) Set the substrate temperature. When the vacuum degree of the system reaches 5×10 ^-4 Pa or above, preheat the furnace filament at low power for 3 minutes, control the heating rate at 15-20°C/min, and raise the temperature to the required temperature for film growth. required temperature.

(5) When the substrate temperature and the pressure in the reaction chamber reach the preset value, first sputter the ZnO-based target to form a layer of ZnO-based thin film on the substrate (40 minutes), and then sputter the Cu target, by controlling the sputtering time to Control the content of Cu in the film. 450 ° C for 30 minutes to ensure sufficient Cu diffusion in the ZnO-based film. the

Detailed ways

(1) Substrate cleaning

The substrate used in this experiment is a 2-inch single-crystal Si (100) substrate, polished on one side, and its resistivity is 1.9-2.6×10 ³ Ω/cm. First, immerse the Si sheet in acetone, place it in an ultrasonic generator for cleaning for one hour, clean it ultrasonically for one hour with anhydrous ethanol, and clean it ultrasonically for one hour with ionized water, then take it out and place it in a constant temperature drying oven for drying.

(2) Installation of target and substrate

Fix the ZnO-based target, the Cu target and the substrate on the corresponding sample holders, adjust the distance between the substrate and the target to 50mm, then tighten the valve and close the vacuum chamber. the

(3) vacuuming

First turn on the cooling water of the molecular pump, turn on the power, turn on the mechanical pump, open the side pumping valve, and turn on the vacuum gauge after a few minutes; when the vacuum degree of the system reaches ^2-3 Pa, close the side pumping valve, open the isolation valve, and start the molecular pump .

(4) Substrate heating

Set the substrate temperature. When the vacuum degree of the system reaches 5×10 ^-4 Pa or above, preheat the furnace wire under low power for 3 minutes, control the heating rate at 15-20°C/min, and raise the temperature to the temperature required for film growth .

(5) Preparation of Cu diffusion-doped ZnO-based samples

When the temperature of the substrate and the pressure in the reaction chamber reach the preset values, the ZnO-based target is first sputtered to form a layer of ZnO-based film on the substrate (40 minutes), and then the Cu target is sputtered, and the sputtering time is controlled to control the amount of time in the film. Cu content. 450 ° C for 30 minutes to ensure sufficient Cu diffusion in the ZnO-based film. the

Claims (2)

1. A method for preparing Cu diffusion-doped ZnO-based semiconductors by pulsed laser deposition is characterized in that: the prepared diffusion layer is a diffusion layer formed by depositing Cu high-temperature diffusion doping into the ZnO base layer, and the prepared material includes substrate, ZnO Base layer, diffusion layer. 2. A method for preparing a Cu diffusion-doped ZnO-based semiconductor by a pulsed laser deposition method according to claim 1, characterized in that: the substrate is a (100) silicon single crystal, and the vacuum degree in the laser pulse cavity is 5×10 ^{− 4} Pa, the deposition temperature is 450°C, the laser frequency is 4Hz, the laser energy is 190kV, the ZnO thin film is sputtered for 40 minutes, the Cu layer is added, the deposition time is 2 minutes, and the temperature is kept at 450°C for 30 minutes to prepare Cu diffusion-doped ZnO matrix. The thin film is formed by cooling the prepared Cu diffusion-doped ZnO-based thin film to room temperature naturally in the cavity.