BICMOS technology on SIMOX wafers

A bipolar transistor comprising:

• a semiconductor substrate;
• a sub-collector in said semiconductor substrate;
• a collector adjacent said sub-collector;
• a patterned isolation region encapsulated within said semiconductor substrate;
• a single crystal extrinsic base over said isolation region;
• and
• an emitter adjacent said single crystal extrinsic base.

A method of manufacturing a bipolar transistor, said method comprising:

• performing an oxygen implant to form a patterned isolation layer underneath a substrate surface;
• forming a single crystalline base over said substrate;
• depositing insulator layers over said single crystalline intrinsic base;
• selectively etching portions of said insulator layers to expose portions of said single crystalline intrinsic base;
• and
• forming a single crystalline base over exposed portions of said single crystalline intrinsic base.

A method of manufacturing a bipolar transistor, said method comprising:

• performing an oxygen implant to form a patterned isolation layer underneath a substrate surface;
• forming a single crystalline intrinsic base over said substrate;
• depositing insulator layers over said single crystalline intrinsic base;
• selectively etching portions of said insulator layers to expose portions of said single crystalline intrinsic base;
• forming a single crystalline extrinsic base over exposed portions of said single crystalline intrinsic base;
• converting any polycrystalline portions and a portion of said single crystalline extrinsic base of said bipolar transistor into oxide by performing a high pressure oxidation process over said single crystalline extrinsic base;
• removing excess portions of said oxide;
• and
• forming an oxide isolation layer over said single crystalline extrinsic base by performing a second high pressure oxidation process over said single crystalline extrinsic base.

A method of manufacturing a bipolar transistor, said method comprising:

• performing an oxygen implant to form a patterned isolation layer underneath a substrate surface;
• forming a single crystalline intrinsic base over said substrate;
• depositing insulator layers over said single crystalline intrinsic base;
• selectively etching portions of said insulators layers to expose portions of said single crystalline intrinsic base;
• forming a single crystalline extrinsic base over exposed portions of said single crystalline intrinsic base;
• converting any polycrystalline portions and a portion of said single crystalline extrinsic base of said bipolar transistor into oxide by performing a high pressure oxidation process over said single crystalline extrinsic base;
• removing excess portions of said oxide;
• and
• forming an oxide isolation layer over said single crystalline extrinsic base by performing a second high pressure oxidation process over said single crystalline extrinsic base, said insulator layers comprise a silicon nitride layer deposited over a silicon dioxide layer.

A method of manufacturing a bipolar transistor, said method comprising:

• performing an oxygen implant to form a patterned isolation layer underneath a substrate surface;
• forming a single crystalline intrinsic base over said substrate;
• depositing insulator layers over said single crystalline intrinsic base;
• selectively etching portions of said insulator layers to expose portions of said single crystalline intrinsic base;
• forming a single crystalline extrinsic base over exposed portions of said single crystalline intrinsic base;
• converting any polycrystalline portions and a portion of said single crystalline extrinsic base of said bipolar transistor into oxide by performing a high pressure oxidation process over said single crystalline extrinsic base;
• removing excess portions of said oxide;
• forming an oxide isolation layer over said single crystalline extrinsic base by performing a second high pressure oxidation process over said single crystalline extrinsic base, said insulator layers comprise a silicon nitride layer deposited over a silicon dioxide layer;
• further comprising:
• removing remaining portions of said silicon nitride layer;
• forming a pair of isolation spacers adjacent a sidewall of said single crystalline extrinsic base and said oxide isolation layer and over said silicon dioxide layer;
• removing exposed portions of said silicon dioxide layer unprotected by said isolation spacers thereby exposing said single crystalline intrinsic base;
• and
• defining an emitter region over said single crystalline intrinsic base.