制备温度对(a-C∶Fe)/Al_2O_3/Si结构光电转换效应影响的研究

EFFECT OF PREPARATION TEMPERATURE ON PHOTOVOLTAIC CHARACTERISTICS OF(a-C∶Fe)/Al_2O_3/Si STRUCTURE

采用脉冲激光沉积法在n-Si(100)衬底上制备氧化铝膜(Al2O3)和不同温度下的铁掺杂非晶碳薄膜(a-C∶Fe)。I-V特性曲线表明:制备的a-C∶Fe/Al2O3/Si异质结结构具有明显的整流特性和光伏效应,碳膜的制备温度对a-C∶Fe/Al2O3/Si结构电池光伏性能有显著影响。合适的沉积温度能显著增大异质结的开路电压和短路电流,进而增大异质结的光电转换效率,在碳膜制备温度为350℃时,异质结获得最佳光电转换效率。当制备温度超过350℃时,电池的开路电压与短路电流大幅度减小。通过对a-C∶Fe膜的拉曼光谱分析显示,随着制备温度的升高,非晶碳膜的结构经历了从类金刚石向类石墨化的转变,从而对电池的光电转换特性造成显著影响。

The iron-doped amorphous carbon films （a-C ： Fe） and Al2O3 films are successfully deposited on n-type silicon （100） substrates by pulsed laser deposition method to prepare a-C： Fe/Al2O3/Si heterojunctions rectifying characteristic and photovohaic effect. The influence of deposited temperatures of a-C： effect of a-C ： Fe/Al2O3/Si is remarkble. The suitable deposited temperatures can obviously enlarge which possess obvious Fe film on photovoltaic the open circuit voltage and short circuit current of heterojunction, also improve its efficiency a lot. When the deposition temperature for a-C ： Fe film is 350 ℃, the cell shows the best PV performance. When the preparation temperature is above 350 ℃, the open circuit voltage and short circuit current are reduced. The Raman spectrum analyses show that a-C ： Fe film have change from diamond-like amorphous carbon to graphite-like amorphous carbon along with the increase of preparation temperatures. Thus it leads to significant influence on photovoltaic characteristics.