Title :
Electron transport in rectifying semiconductor alloy ramp heterostructures
Author :
Tait, Gregory B. ; Westgate, Charles R.
Author_Institution :
US Naval Res. Lab., Washington, DC, USA
fDate :
6/1/1991 12:00:00 AM
Abstract :
The electron transport properties of AlGaAs ramp diodes are investigated using a physical model which combines current transport through the heterostructure bulk with current across the abrupt heterointerface in a fully self-consistent numerical approach. Transport at the abrupt material discontinuity is described by thermionic and thermionic-field emission processes, whereas transport in regions of smoothly varying alloy composition is modeled by diffusion-drift mechanisms. Several devices whose bandgaps are graded over several thousand angstroms have been fabricated by molecular beam epitaxy (MBE) and tested at room and liquid-nitrogen temperatures. The experimentally observed rectification properties are compared with the simulated results over a wide range of DC bias. Through appropriate choice of alloy composition and doping profiles, majority carrier devices based on internal (bulk) barriers may be realized
Keywords :
III-V semiconductors; aluminium compounds; gallium arsenide; molecular beam epitaxial growth; semiconductor device models; semiconductor diodes; 300 K; 77 K; AlGaAs ramp diodes; MBE; abrupt heterointerface; abrupt material discontinuity; diffusion-drift mechanisms; doping profiles; electron transport properties; graded bandgap; heterostructure bulk; liquid-nitrogen temperatures; majority carrier devices; molecular beam epitaxy; physical model; range of DC bias; rectification properties; rectifying semiconductor alloy ramp heterostructures; room temperature; semiconductors; thermionic-field emission; Composite materials; Electrons; Molecular beam epitaxial growth; Photonic band gap; Semiconductor diodes; Semiconductor materials; Semiconductor process modeling; Temperature; Testing; Thermionic emission;
Journal_Title :
Electron Devices, IEEE Transactions on
