单靶溅射制备铜锌锡硫薄膜及原位退火研究  

Fabrication of Cu_2ZnSnS_4 thin films by sputtering quaternary compound target and the research of in-situ annealing

作　　者：赵其琛 郝瑞亭[1] 刘思佳[1] 刘欣星 常发冉 杨敏[1] 陆熠磊 王书荣[1] 

机构地区：[1]云南师范大学太阳能研究所,可再生能源材料先进技术与制备教育部重点实验室,云南省农村能源工程重点实验室,昆明650500

出　　处：《物理学报》2017年第22期250-256,共7页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:61774130,11474248,61176127,61006085);国际科技合作重点项目(批准号:2011DFA62380);教育部博士点基金(批准号:20105303120002)资助的课题~~

摘　　要：采用衬底加热溅射铜锌锡硫(CZTS)四元化合物单靶制备CZTS薄膜,并研究原位退火对制备薄膜的影响.结果表明:在溅射结束后快速升温并保持一段时间,所得到的样品相比于未原位退火的CZTS薄膜结晶质量更好,且表面更平整致密;原位退火后的CZTS薄膜太阳电池性能参数也相应地有所提升,其开路电压(V_(OC))为575 mV,短路电流密度(J_(SC))为8.32 mA/cm^2,光电转换效率达到1.82%.The kesterite compound Cu_2ZnSnS_4（CZTS） is one of the most interesting materials for absorber layers of thin-film solar cells, not only because it is composed of earth abundant and non-toxic elements, but also owing to the fact that its absorption coefficient is high（on the order of 10~4 cm^（-1）） and its optimal band gap is 1.5 eV for single-junction solar cells.Plenty of methods are used to deposit the CZTS layer, such as evaporation, sputtering, spray-pyrolysis, sol-gel,pulsed laser deposition and electro-chemical deposition. Among these methods, sputtering is considered as one of the most viable deposition techniques for producing a large-scale panel of thin film solar cells with demonstrable productivity and easy adjustment. In this paper, Cu_2ZnSnS_4 thin films are prepared by in-situ annealing after being sputtered with a quaternary compound target. This technology can reduce the extrinsic defects in the thin film. It is desirable to control the growth of grain boundary, increase grain size and make the thin film more compact and smooth.The in-situ annealing is a method which can heat a work piece fast to a certain temperature and maintain the temperature for some time after sputtering. As is well known, one of the major reasons for affecting CZTS device performance is the low open circuit voltage（V_（oc））, and it is also a challenge to obtain a high value because there are a lot of defect states at the grain boundaries. The experiment shows that using the method of in-situ annealing after sputtering can obtain large size grains and smooth and compact surface. The obtained thin films are Cu-poor, Zn-rich and Sn-poor, which can restrain the Cu vacancies（V_（Cu）） and anti-site defects（Cu_（Zn）,Sn_（Zn）,and Sn_（Cu））. The free carrier concentration（N_A） increases with the increase of Zn content, while the open circuit voltage of CZTS solar cells increases with the increase of N_A.In order to develop CZTS solar cells based on the thin films, the n-type CdS buffer laye

关 键 词：铜锌锡硫 磁控溅射 原位退火 太阳电池 

分 类 号：O484[理学—固体物理]