CdTe 태양전지 박막의 어닐링 조건 최적화

Abstract

CdTe thin film solar cell is attracting a great deal of attention owing to its conversion efficiency and production cost compared to the conventional silicon solar cell. CdTe thin film is also well known that it has the suitable characteristics with the optimal band gap energy (about 1.4eV) for solar energy absorption, high light-absorption capability and low cost requirements for producing solar cells. CdTe is one of the most convincing materials for thin-film solar cells shaped as the p-CdTe/n-CdS-doped heterostructure. The conductivity type of sputtering-deposited CdTe thin film was different in my experiments compared to the well-known property. In this paper, the effects of annealing treatment were investigated on the thin film characteristics including the conductivity type in the hydrogen or oxygen ambients. The effects of hydrogen and oxygen annealing treatment on the electrical and optical properties of CdTe thin film were investigated by UV-Visible spectrophotometer and Hall effect measurement. The role of hydrogen and oxygen was examined by some analytical methods including X-ray diffraction (XRD). The optical and electrical properties of CdTe thin film such as optical transmittance, absorption coefficient, carrier mobility, resistivity and carrier density were also measured and analyzed. Through the comparison from these result by studying the efficiency influenced by annealing process of CdTe thin film on the electrical and optical properties of CdTe thin film solar cell, it is to find the relationship between the surface uniformity and the photo voltaic properties of CdTe thin film solar cell as well as the optimized process conditions for application of CdTe solar cell's fabrication of annealing process.