Extension of the lumped bulk device model to incorporate the process of domain dissolution

A lumped model capable of representing domain nucleation, modulation, and quenching in n-GaAs has previously been reported. In the present paper an algorithm is proposed which successfully describes the process of domain dissolution. An analytical description of the mechanisms involved is achieved by characterizing the shape of a stable domain and by postulating the existence of an "apparent" domain which maintains the stable-domain shape while passing across an ideal anode boundary. The actual domain is then treated as that portion of the apparent domain remaining within the device. It is shown that during the dissolution process the apparent domain undergoes a growth mechanism due to the rise in device current. A complete mathematical description of the phenomena is subsequently incorporated into the original lumped model and simulated with the digital program BULKSIM. Device studies with the extended model have produced results exhibiting exceptional agreement with a distributed model simulated by the program BULK-D.