SELECTIVE EPITAXIAL-GROWTH OF SILICON BY THE AC TECHNIQUE .3. LATERALOVERGROWTH STRUCTURES

During studies of the alternating cyclic, A.C., technique for the sele ctive epitaxial growth of silicon, lateral epitaxial overgrowth (ELO) structures were observed following non A.C, reference depositions in a low pressure hot wall system. Experiments were conducted at 2.5 Torr, 950 degrees C, H-2/SiCl4 = 50, Ar/H-2 = 9, with H-2 = 2 slpm, SiCl4 = 0.04 slpm, and Ar = 18 slpm. Patterned 0.22 to 0.35 mu m thermal oxid e covered silicon substrates with the oxide coverage ranging from 10 t o 70% were employed. It was found that if the growth conditions and th e oxide mask and exposed silicon opening sizes are properly chosen, vo id-free ELO structures are obtainable.