The electron impact ionization rate and breakdown voltage in GaAs/Ga/sub 0.7/Al/sub 0.3/As MQW structures

The electron impact ionization rate ( alpha ) and breakdown voltage (V/sub BD/) experimentally measured in a p/sup +/-i-n/sup +/ diode structure with a GaAs/Ga/sub 0.7/Al/sub 0.3/As multiple quantum-well (MQW) i region are discussed. For structures with GaAs wells of 100 AA and barriers that vary from 7 to 60 AA in thickness, it is found that alpha is always less than alpha in bulk GaAs and that it decreases with increasing barrier thickness. The normalized V/sub BD/ also increases with increasing barrier thickness, confirming a decreasing ionization rate.>