Avalanche multiplication and noise in submicron Si p-i-n diodes

We have measured avalanche multiplication and noise in Si p- i-n diodes with avalanche widths, w, of 0.12 micrometers , 0.18 micrometers and 0.32 micrometers , both for pure electron and mixed carrier injection. Multiplication and excess noise measurements were also performed with hole injection on a n+-i-p+ diode with w equals 0.84 micrometers . Pure electron initiated avalanche noise results were found to be almost indistinguishable in all three layers. The excess noise factor increases dramatically with increasing w when the injection is mixed.