Determination of the minority-carrier base lifetime of junction transistors by measurements of basewidth-modulation conductances

A method for determining the minority-carrier lifetime in the base of a bipolar transistor is described that involves measurement of the low-frequency, small-signal output conductance G
o
and reverse transconductance G
r
, which arise from basewidth modulation. It involves also determining the base transit time either from calculations based on the base doping profile or from measurements at the transistor terminals. To illustrate the method, it is applied to transistors having considerably different base lifetimes.