Study Of Amorphous Crystalline Silicon Film And HIT Solar Cell Depositing With RF-PECVD

The preparation of the undoped microcrystalline silicon (a-Si:H ) films with the high deposition rate were carried out by plasma enhanced vapor deposition (PECVD). The microstructure and the growth mechanism of a-Si:H films as well as the fabrication of solar cells were studied. The main results are as follows:1.Investigating on the influence of deposition parameters on conductivity and defect density of n-a-Si:H. The n-type a-Si:H thin films with varying crystalline fraction and conductivity are achieved. The maximum of conductivity is 20S/cm. the compact problems of silicon thin films deposited by PECVD process were investigated. In order to achieve high stability and compact silicon thin films in PECVD process, higher back vacuum, lower substrate temperature and lower crystalline fraction are necessary.2.The performance of heterojunction solar cell was simulated with different band gap, thickness of intrinsic layer and defect density via AFORS-HET, Version 2.2. It was found that the efficiency increased by inserting a intrinsic layer,but it drops with the increase of its thickness.The short circuit current increase with the band gap,but it also drops when the band gap reaches some value.The band offset of the emitter had no effect on the short circuit current,but the voltage increased with its increase. The voltage decrease rapidly with the defect density .3.The effect of the a-Si:H p-layer prepared by PECVD on the performance of the solar cell has been investigated. By optimizing a-Si:H p-layer parameters, conversion efficiency of 9.8% for the structure of Al/ ITO/a-Si:H(p)/c-Si(n)/Al was fabricated without texturing. The comparisons of the solar cell performances using different surface passivation techniques have been made. The H plasma passivation enhanced JSC. Inserting an thin a-Si:H layer between p-layer and c-Si, VOC was improved.