SiGe-base PNP transistors with dramatically reduced valence band barrier effects on the DC and AC characteristics were fabricated with an N-type ultra high vacuum/chemical vapor deposition (UHV/CVD) epitaxial base in a polysilicon emitter technology. The transistors have ideal Gummel characteristics, high current gain, and cutoff frequencies of 50 to 55 GHz. These results demonstrate that SiGe-base PNP transistors are superior to Si-base or III-V PNP devices and comparable to the fastest Si-base NPN transistors. Despite their high Ge-content, the strained bases remain stable after a 950°C furnace anneal or a 975°C rapid thermal processing (RTP) anneal.
|Number of pages||2|
|Journal||Digest of Technical Papers - Symposium on VLSI Technology|
|State||Published - Dec 1991|
|Event||1991 Symposium on VLSI Technology - Oiso, Jpn|
Duration: 28 May 1991 → 30 May 1991