A Novel BJT Structure Implemented Using CMOS Processes for High-Performance Analog Circuit Applications

In this paper, a novel bipolar junction transistor (BJT) structure is proposed for high matching characteristics and its performance is compared with a conventional BJT structure. Although the proposed BJT matching structure indicates a decrease of collector current density
$J_{C}$
and current gain
$\beta$
of about 5.36% and 1.02% compared with those of the conventional BJT structure, the matching characteristics of the collector current
$(A_{\rm IC})$
and the current gain
$(A_{\beta})$
for the proposed structure are improved by about 31% and 24%. The improved matching characteristic of the proposed structure is believed to be due to the reduced effect of the deep n-well or the reduced current path from emitter to collector.