UNDOPED AND DOPED CRYSTALLINE SILICON FILMS OBTAINED BY ND-YAG LASER

In this paper, we present results of the role of laser beam energy and shot density on the electro-optical and structural properties of undo ped and doped recrystallized amorphous silicon thin films, generated b y pulsed Nd-YAG laser (lambda = 532 nm). The data reveal that the stru cture and electrical characteristics of the recrystallized thin films are mainly dependent on the energy and shot density of the laser beam, while the morphology of the obtained films are mainly governed by the number of shots used. The data also show that the electrical conducti vity of undoped and doped recrystallized films can be varied up to 6 o rders of magnitude, by the proper choice of the recrystallization cond itions. Doped samples with conductivities in the amorphous states in t he range of 10(-5) Omega(-1) cm-l present, after recrystallization, co nductivities of about 300 Omega(-1) cm(-1). The SEM micro-chemical ana lysis also shows that the obtained crystalline grains are constituted by pure silicon. (C) 1998 Elsevier Science S.A.