Borsenic bipolar process

A new process utilizing simultaneous diffusion of Boron and Arsenic (Borsenic) from doped oxide, to fabricate high performance bipolar transistors has been developed. The doped oxide is deposited at low temperature by oxidation of SiH4, B2H6and AsH3. Since As diffuses much slower than B in Si, by heating the doped oxide at high temperatures n⁺-p-n structures have been obtained. By varying the time and temperature of diffusion or by varying As or B content in the oxide, we have fabricated from extremely shallow (e.g. ) to fairly deep (e.g ) bipolar transistors. Details of the fabrication process and properties of the transistors are presented here.