Title :
The electron impact ionization coefficient in a GaAs-Ga0.7 Al0.3As multiple quantum well structure
Author :
David, J.P.R. ; Roberts, J.S. ; Marsland, J.S. ; Robson, P.N.
Author_Institution :
Dept. of Electron. & Electr. Eng., Sheffield Univ., UK
Abstract :
The electron ionization coefficient (α) is experimentally measured in a p-i-n diode structure with a multiple quantum well (MQW) `i´ region as the well and barrier dimensions are systematically varied. Assuming that α⩾β (hole ionization coefficient) it is shown that α can be obtained accurately for low electric-fields if only the electron initiated multiplication is known. A number of structures are grown with 100 Å wells and Ga0.7Al0.3As barriers varying in thickness from OÅ (bulk GaAs) to 60 Å. In all the structures considered α is found to be less than that for GaAs and similar to that for a uniform GaAlAs alloy obtained by complete intermixing of the wells and barriers
Keywords :
III-V semiconductors; aluminium compounds; gallium arsenide; impact ionisation; semiconductor device models; semiconductor diodes; semiconductor quantum wells; 0 to 60 A; Ga0.7Al0.3As barriers; GaAs-Ga0.7Al0.3As; MQW; barrier dimensions; electron impact ionization coefficient; electron initiated multiplication; electron ionization coefficient; hole ionization coefficient; low electric-fields; multiple quantum well structure; p-i-n diode structure; well dimensions;
Conference_Titel :
Heterojunction and Quantym Well Devices: Physics, Engineering and Applications, IEE Colloquium on
Conference_Location :
London
