摘要 |
A method of manufacturing a bipolar transistor in a P-type substrate, including the steps of forming in the substrate a first N-type area; forming by epitaxy a first silicon layer; forming in this first layer, and substantially above the first area a second heavily-doped P-type area separate from the second area; forming at the periphery of this second area a third N-type area; forming by epitaxy a second silicon layer; forming a deep trench crossing the first and second silicon layers, penetrating into the substrate and laterally separating the second area from the third area; and performing an anneal such that the dopant of the third area is in continuity with that of the first area.
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