Inordertoimprovetheefficiency,stabilityofsilicon basesolarcells,andtoloweritscosts,tandemstruc ture[1]andlight traptechnique[2]havebeenwidelyem ployed.Recently,moreandmoreattentionshavebeenpaidtomicrocrystallinesiliconμc Si:H4filmdeposited atlowtemperaturebecauseofitspromisingapplication tostablehighefficiencysolarcells,andsomeremarkableprogresseshavebeenmadeinμc Si:Hthinfilmdeposi tionanditsapplicationinsolarcells[3 7].Ingeneral,VHF PECVDtechnique,basedonVHF generatedplasma,ismorec…