Title :
A low dark current, high-speed GaAs/Al/sub 0.3/Ga/sub 0.7/As heterostructure Schottky barrier photodiode
Author :
Lee, D.H. ; Li, S.S. ; Paulter, N.G.
Author_Institution :
Dept. of Electr. Eng., Florida Univ., Gainesville, FL, USA
fDate :
5/1/1989 12:00:00 AM
Abstract :
A high-speed and high-sensitivity planar GaAs/Al0.3Ga0.7As heterostructure Schottky barrier photodiode is discussed. Using a highly doped Al0.3Ga0.7As buffer layer between the active layer and semi-insulating GaAs substrate, the series resistance and the undesired diffusion tailing are greatly reduced. Studies of surface stabilization and antireflection coating, performed to reduce the reverse-bias dark current and the reflection loss, resulted in significant improvement in the sensitivity of the photodiode. The measured internal quantum efficiency and responsivity are 60-77% and 0.47-0.6 A/W, respectively, for the wavelength range of 0.5-0.84 μm. A risetime of 8.5 ps and an FWHM of 16 ps were measured by using a sampling/correlation method.
Keywords :
III-V semiconductors; Schottky-barrier diodes; aluminium compounds; antireflection coatings; gallium arsenide; high-speed optical techniques; integrated optoelectronics; optical communication equipment; photodetectors; photodiodes; 0.5 to 0.84 micron; 60 to 77 percent; 8.5 ps; FWHM; GaAs-Al0.3Ga0.7As; active layer; antireflection coating; heterostructure Schottky barrier photodiode; high-speed high-sensitivity planar photodiode; highly doped buffer layer; integrated optoelectronics; internal quantum efficiency; low dark current; reflection loss; responsivity; reverse-bias dark current; risetime; sampling/correlation method; semi-insulating substrate; semiconductor; sensitivity; series resistance; surface stabilization; undesired diffusion tailing; wavelength range; Buffer layers; Coatings; Dark current; Electrical resistance measurement; Gallium arsenide; Photodiodes; Reflection; Schottky barriers; Surface resistance; Wavelength measurement;
Journal_Title :
Quantum Electronics, IEEE Journal of
