Methods of decreasing the noise and increasing the computational effic
iency in Monte Carlo simulations of semiconductor devices are investig
ated. A lookup table approach to the charge assignment to mesh points
has been implemented which is independent of the complexity of the ass
ignment function. Using this approach reduces the CPU time of the char
ge assignment to about one third. Potential fluctuations in low held r
egions are compared for different assignment function, which shows the
advantage of using more complex schemes than those generally used. Re
sults from a full band Monte Carlo simulation of a submicron Schottky
diode are presented and the values of the current density for differen
t assignment schemes are compared, showing a lower noise for the highe
r order schemes. Statistical enhancements by splitting of superparticl
es in the depletion region has been investigated. The combination of a
high order assignment scheme and statistical enhancement by splitting
decreases simulation runtimes considerable for a given noise toleranc
e.