【摘要】 用MOCVD方法在Si基片上生长了Al掺杂的SiC薄膜,发现三甲基铝(TMA)源载气流量与硅烷流量之比的大小,会决定薄膜的导电类型。用XPS方法测试样品后发现,TMA载气流量与硅烷流量比直接影响Al原子在SiC薄膜中的含量。Al含量在1.5%以下,Al原子在SiC薄膜中主要以填隙形式(Ali)存在,薄膜显示出n型;而Al含量在1.5%～3%之间的时候,Al原子主要以替位Si(AlSi)的形式存在,薄膜显示出p型。继续增加掺杂源的流量,所得SiC薄膜结晶质量会变得较差,电阻也变得较高。更多还原

【Abstract】 Al-doped SiC films are deposied on silicon substrates by metal-organic chemical vapor deposition (MOCVD).The flow rate ratio between SiH4 and TMA,which determines the aluminium content in the SiC films,plays an important role in determining the conduction type of SiC films.XPS spectrum shows that aluminium atoms are institials in major and the SiC films are n-type when the aluminium content is less than 1.5% and that aluminium atoms substitute silicon atoms in major and the films are p-type when the aluminium content is between 1.5% and 3.0%,and the SiC films becomes high resistivity and the crystall quality becomes worse as the aluminum content exceeds 3%.更多还原