JPS6433920A - Growth method of semiconductor film - Google Patents

Abstract

PURPOSE:To take a contact to a base without lengthening the growth time from a conductive film buried to a sidewall section, not the surface, and to reduce parasitic capacitance by growing approximately a section where the thickness of a selective epitaxial growth film reaches the cross section of a polycrystalline semiconductor layer under the state in which a large quantity of HCl gas are added. CONSTITUTION:A first dielectric insulating layer 102, a polycrystalline semiconductor layer 104 and a second dielectric insulating layer 106 are formed onto a semiconductor substrate 100 in succession, an opening section 108, whose cross section has the polycrystalline semiconductor layer 104, is shaped, and selective epitaxial growth is conducted in an atmosphere containing HCl gas on the exposed substrate semiconductor surface. Approximately a section where the thickness of a selective epitaxial growth film reaches the cross section of the polycrystalline semiconductor layer 104 is grown under the state in which a large quantity of HCl gas are added at that time. Consequently, the polycrystalline semiconductor film 104 is etched, and only a selective epitaxial growth film 103 is grown. The selective epitaxial growth film 103 is grown in the cross direction on the insulating layer 102, and brought into contact with the polycrystalline semiconductor film 104, thus forming a semiconductor film having structure as shown in the figure.