关于多孔硅

多孔硅在太阳电池中应用有着很大的 潜力。

SolarEnergyMaterials&SolarCells65(2001)477}485

Poroussiliconasanintermediatelayer

forthin-"lmsolarcell

R.Bilyalov*,L.Stalmans,G.Beaucarne,R.Loo,M.Caymax,

J.Poortmans,J.Nijs

IMECvzw,Kapeldreef75,B-3001Leuven,Belgium

Abstract

Thepotentialofporoussilicon(PS)withdualporositystructureasanintermediatelayerforultra-thin"lmsolarcellsisdescribed.Itisshownthatadouble-layeredPSwithaporosityof%allowstogrowepitaxialSi"lmatmediumtemperature(7253}8003C)andatthesametimeservesasagettering/di!usionbarrierforimpuritiesfrompotentiallycontaminatedlow-costsubstrate.A3.5 mthin-"lmcellwithreasonablee$ciencyisrealizedusingsuchaPSintermediatelayer. 2001ElsevierScienceB.V.Allrightsreserved.

Keywords:Poroussilicon;Thin"lms;Sisolarcells

1.Introduction

Thin-crystallinesiliconsolarcellshaveagreatpotentialforphotovoltaicapplica-tions.Theuseoflow-costSi-basedsubstratessuchasmetallurgicalgradeSi(MG-Si)

[1]orSisheetsfrompowder[2]looksveryattractivefromtheviewpointofcost.Ontheotherhand,thesematerialsarecontaminatedbydi!erentimpurities(particularlytransitionmetals),whichmightdi!useintotheactiveSilayerduringtheCVDprocessandresultinadegradationofthesolarcellcharacteristics.Secondly,thesesubstratescannotactasabacksidere#ector,whichishowevercrucialforultra-thin-"lmsolarcells.

OnepossiblewaytoovercometheseproblemsistousePSasanintermediatelayerbetweensubstrateandthinSi"lm.ItwasshownalreadythatasinglePSlayerwith*Correspondingauthor.Tel.:#32-16-281270;fax:#32-16-281501.

E-mailaddress:bilyalov@imec.be(R.Bilyalov).

AlsoProfessoratKatholiekeUniversiteitLeuven,ElectrotechnicalDepartment,

Belgium.

0927-0248/01/$-seefrontmatter 2001ElsevierScienceB.V.Allrightsreserved.

PII:S0927-0248(00)00130-6