From polycrystalline to single crystalline silicon on glass

Thin film transistors and solar cells from polycrystalline silicon suffer f rom the influence of grain boundary charges. This contribution reviews thre e possibilities to suppress these charges: (i) by the selection of speciall y oriented grain boundaries in small-grained silicon. Analysis of solar cel ls demonstrates that (110)-textured films must contain electrically low-act ive boundaries. (ii) Special laser crystallization yields large-grained Si of excellent quality. (iii) Transfer techniques allow one to fabricate sing le crystal films on foreign substrates. In addition to these three methods, we discuss joined-wafer silicon for growth of single crystalline Si films and layers of essentially unlimited size. (C) 2001 Elsevier Science B.V. Al l rights reserved.