Title :
A low-noise and wide-bandwidth InGaAs/InAlAs superlattice APD
Author :
Kagawa, Toshiaki ; Kawamura, Yuichi ; Asai, Hiromitsu ; Naganuma, Mitsueu ; Mikami, Osamu
Author_Institution :
NTT, Kanagawa, Japan
Abstract :
An InGaAs-InAlAs superlattice avalanche photodiode (APD) was fabricated by MBE (molecular beam epitaxy), and impact ionization rates, excess multiplication noise, and high-frequency response were measured. The electron ionization rate ( alpha ) is enhanced by the large conduction band offset. The ratio of alpha / beta is as large as 29 at an electric field of 2.2*10/sup 5/ V/cm, where beta is the hole ionization rate. As a result of the enhanced ionization rate ratio, the excess multiplication noise is quite small and fits the theoretical curve with an effective ionization rate ratio of 0.05. The 3-dB bandwidth is 4 GHz at a multiplication factor of 16. This shows that the carrier pileup is negligible in a high electric field. The 3-dB bandwidth is limited not by the gain-bandwidth limit but by the electron diffusion time in the photoabsorption layer.<>
Keywords :
III-V semiconductors; aluminium compounds; avalanche photodiodes; electron device noise; gallium arsenide; indium compounds; molecular beam epitaxial growth; semiconductor superlattices; 4 GHz; InGaAs-InAlAs; MBE; bandwidth; carrier pileup; conduction band offset; electron diffusion time; electron ionization rate; excess multiplication noise; high electric field; high-frequency response; hole ionization rate; impact ionization rates; low noise APD; molecular beam epitaxy; multiplication factor; photoabsorption layer; semiconductors; superlattice APD; superlattice avalanche photodiode; wide-bandwidth; Avalanche photodiodes; Bandwidth; Electrons; Impact ionization; Indium compounds; Indium gallium arsenide; Molecular beam epitaxial growth; Noise measurement; Signal to noise ratio; Superlattices;
Conference_Titel :
Electron Devices Meeting, 1989. IEDM '89. Technical Digest., International
Conference_Location :
Washington, DC, USA
Print_ISBN :
0-7803-0817-4
DOI :
10.1109/IEDM.1989.74157
