High frequency breakdown in diffused transistors

In addition to offering such desirable performance characteristics as very large bandwidth and appreciably high current gain, transistors manufactured by diffusion techniques possess a high frequency voltage capability that is significantly in excess of the breakdown voltage which materializes under quiescent operating conditions. This paper attributes voltage capability enhancement in diffused transistors to the excess phase which is evidenced in the current gain characteristics of these devices. An "excess breakdown function," developed in this paper, permits direct calculation of the factor by which quiescent breakdown specifications can be safely exceeded at given frequencies of operation.