| Lead chalcogenides (PbS,PbSe and PbTe) are narrow band gap semiconductors which have shown great promise in the field of IR photodetectors, diode lasers and thermoelectric devices. Lead telluride (PbTe) is a narrow band gap (0.31 eV) semiconductor with a rock-salt crystal structure. Because of high quantum efficiencies, a low noise level at working temperature, and an ability to tune the peak wavelength by adjusting the alloy composition, PbTe is a great candidate material for infrared (IR) optoelectronics devices (e.g., IR detector and mid-infrared quantum well laser diode). PbTe is an important high-refractive-index material in the field of infrared optical thin films devices, because of refractive-index of 5.5 and wide transparent waveband. In addition, PbTe is among the most efficient thermoelectric materials in the intermediate range of temperature (500-900 K) because of its high thermoelectric figure-of-merit, a high melting point, good chemical stability, and a low vapor pressure. Lead telluride has important applications on the aviation and aerospace, environmental protection, medical, laser technology and solar energy technology and other high-tech fields, and has been applied on the limousine as thermoelectric cooling materials which can achieve non-polluting small-scale refrigeration. Especially with the in-depth study of quantum structure solar cells, PbTe quantum dots are expected to greatly improve the conversion efficiency of solar cells.Various methods, including molecular beam epitaxy (MBE), vacuum evaporation, electrodeposition technique, pulsed laser deposition (PLD) and magnetron sputtering have been used to produce PbTe thin films. Among these techniques, magnetron sputtering is recognized as an attractive technique because of its many advantages, including low temperature, high-speed, cost-effectiveness, large-scale production, control of thickness of materials, and repeatability.In this paper, PbTe nanoflims are prepared by RF magnetron sputtering. The effect of different parameters on the structure of PbTe nanofilms is investigated. The main research results illustrate as follows:1. PbTe thin films prepared by RF magnetron sputtering are investigated by X-ray diffraction. The main conclusions obtained illustrate as follows:(1) When the substrate isn't heated, PbTe thin films have a preferred orientation along the <100> direction. And the films prepared at 30 W sputtering power and 10 min have a better preferred orientation.(2) Substrate temperature can affect the crystallization quality. The films have an obvious preferred orientation, when the substrate isn't heated, and heated to 100℃and 400℃, and the films have a best preferred orientation when not heated. The films don't have an obvious preferred orientation in the case of 200 and 300℃.(3) Annealing can improve the crystallization quality. Texture of <100> enhances and grain increases as the annealing temperature from room temperature to 500℃.2. The effect of annealing duration and substrate temperature on the microstructure of sputtering films is investigated by XRD and AFM.The structure and surface morphology of sputtering films are greatly affected by annealing duration and substrate temperature. When the films are annealed at 400℃, the films for 15 min annealing duration have the most smooth surface. The films at the substrate temperature of 100℃have the most smooth ,and XRD analysis reveal that the films have a best preferred orientation when the substrate temperature is cooler.3. PbTe nanoparticle films are prepared by RF magnetron sputtering and annealing in the vacuum chamber.
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