Title :
Si/GexSi/sub 1-x/ heterojunction bipolar transistors with the GexSi/sub 1-x/ base formed by Ge ion implantation in Si
Author :
Lombardo, S. ; Pinto, A. ; Raineri, V. ; Ward, P. ; Rosa, G. La ; Privitera, G. ; Campisano, S.U.
Author_Institution :
Istituto di Metodologie e Tecnologie per la Microelettronica, CNR, Catania, Italy
Abstract :
We have fabricated n-p-n, Si/Ge/sub 2/Si/sub 1-x/ heterojunction bipolar transistors (HBTs) with the Ge/sub x/Si/sub 1-x/ base formed by high-dose Ge implantation followed by solid phase epitaxy. The fabrication technology is a standard self-aligned, double polysilicon process scheme for Si with the addition of the high-dose Ge implantation. The transistors are characterized by a 60 mn-wide neutral base with a Ge concentration peak of /spl ap/8 at.% at the base-collector junction. The HBTs show good electrical characteristics and compared to Si homojunction transistors show lower base resistance, larger values of current gain, and a lower emitter-to-collector transit time.
Keywords :
Ge-Si alloys; elemental semiconductors; germanium; heterojunction bipolar transistors; ion implantation; semiconductor materials; silicon; solid phase epitaxial growth; Ge/sub x/Si/sub 1-x/ base; Si-GeSi; Si/Ge/sub 2/Si/sub 1-x/ HBT; base resistance; current gain; emitter-to-collector transit time; fabrication technology; heterojunction bipolar transistors; high-dose Ge implantation; n-p-n devices; self-aligned double polysilicon process; solid phase epitaxy; Doping; Electrical resistance measurement; Epitaxial growth; Heterojunction bipolar transistors; Implants; Insulation; Ion implantation; Rapid thermal annealing; Rapid thermal processing; Substrates;
Journal_Title :
Electron Device Letters, IEEE
