CAJ | 학술논문

氢化非晶氧化硅(α-SiOx∶H)是一种优质的硅片表面钝化材料.采用PECVD法,以 SiH4、CO2和 H 2作为气源制备α-Si O x∶H 薄膜钝化 Cz-Si 表面,研究了沉积气压和CO2∶SiH4流量比对钝化效果的影响规律及作用机制.采用准稳态光电导法测试了硅片的有效少子寿命并依此计算出其表面复合速率以对薄膜的钝化效果进行定量表征,采用光谱型椭偏仪测试了样品的介电常数虚部ε2谱对样品微观结构进行了定性分析.结果表明,(1)在所研究范围内,氧掺入非晶硅薄膜使得薄膜结构趋向非晶化,沉积气压主要对薄膜中的空位浓度造成影响,而 CO2/SiH4流量比的增加可增加薄膜中的 H 含量并改变了硅氢键的结构,从而影响薄膜的钝化效果；(2)在 CO2/SiH4流量比为3．0/3．0 mL/min,沉积气压为22 Pa 条件下获得了最优钝化效果,钝化后硅片有效少子寿命为975μs,表面复合速率为3．9 cm/s.
경화비정양화규(α-SiOx∶H)시일충우질적규편표면둔화재료.채용PECVD법,이 SiH4、CO2화 H 2작위기원제비α-Si O x∶H 박막둔화 Cz-Si 표면,연구료침적기압화CO2∶SiH4류량비대둔화효과적영향규률급작용궤제.채용준은태광전도법측시료규편적유효소자수명병의차계산출기표면복합속솔이대박막적둔화효과진행정량표정,채용광보형타편의측시료양품적개전상수허부ε2보대양품미관결구진행료정성분석.결과표명,(1)재소연구범위내,양참입비정규박막사득박막결구추향비정화,침적기압주요대박막중적공위농도조성영향,이 CO2/SiH4류량비적증가가증가박막중적 H 함량병개변료규경건적결구,종이영향박막적둔화효과；(2)재 CO2/SiH4류량비위3．0/3．0 mL/min,침적기압위22 Pa 조건하획득료최우둔화효과,둔화후규편유효소자수명위975μs,표면복합속솔위3．9 cm/s.
Amorphous hydrogenated silicon sub-oxide (α-SiOx∶H)is an excellent passivation material for sili-con wafer.In this paper,theα-SiOx∶H films were deposited to passivate n-type Cz-Si wafer by PECVD meth-od,SiH4 ,CO2 and H2 were used as precursors.The deposition pressure and the ratio of the CO2/SiH4 flow rate (RCO2/SiH4 )were optimized and their operation mechanisms on the passivation effect were analyzed.Quasi-steady state photoconductance method and spectroscopic ellipsometer were used to test the effective lifetime and imagi-nary part of the dielectric function (ε2 )of the passivated wafers.It was found that:(1)In this study,the doped oxygen in the films makes them amorphized.The operation mechanisms on the passivation effect of the two pa-rameters were different.Generally,the deposition pressure affects the void fraction in the films and RCO2/SiH4 af-fects the hydrogen fraction and structure.(2)The highest effective lifetime 975μs and the lowest surface re-combination 3.9 cm/s were gotten when RCO2/SiH4 was 3.0/3.0 mL/min and the deposition pressure was 22 Pa.