DEVICE MODELING FOR THE 1990S

As semiconductor technology continues to evolve, numerical modelling o f the devices' electrical behaviour is becoming increasingly important . In this contribution, the model hierarchy which exists for the descr iption of current now in a semiconductor device is briefly reviewed. T he strengths and restrictions of each model are critically examined. P resently, drift-diffusion based simulation programs are considered as the workhorse tools in engineering. However, an enormous research effo rt is going on, with the aim of improving alternatives such as the hyd rodynamic model, the spherical harmonics expansion method and the Mont e Carlo technique. Examples of recently proposed improvements in that field are described.