Title :
Gain-bandwidth characteristics of thin avalanche photodiodes
Author :
Hayat, Majeed M. ; Kwon, Oh-Hyun ; Pan, Yi ; Sotirelis, Paul ; Campbell, Joe C. ; Saleh, Bahaa E A ; Teich, Malvin Carl
Author_Institution :
Dept. of Electr. & Comput. Eng., New Mexico Univ., Albuquerque, NM, USA
fDate :
5/1/2002 12:00:00 AM
Abstract :
The frequency-response characteristics of avalanche photodiodes (APDs) with thin multiplication layers are investigated by means of a recurrence technique that incorporates the history dependence of ionization coefficients. In addition, to characterize the autocorrelation function of the impulse response, new recurrence equations are derived and solved using a parallel computer. The mean frequency response and the gain-bandwidth product are computed and a simple model for the dependence of the gain-bandwidth product on the multiplication-layer width is set forth for GaAs, InP, Al0.2Ga0.8As, and In0.52Al0.48 As APDs. It is shown that the dead-space effect leads to a reduction (up to 30%) in the bandwidth from that predicted by the conventional multiplication theory. Notably, calculation of the power-spectral density of the photocurrent reveals that the presence of dead space also results in a reduction in the fluctuations in the frequency response. This result is the spectral generalization of the reduction in the excess noise factor in thin APDs and reveals an added advantage of using thin APDs in ultrafast receivers
Keywords :
III-V semiconductors; aluminium compounds; avalanche photodiodes; frequency response; gallium arsenide; impact ionisation; indium compounds; optical receivers; semiconductor device models; semiconductor device noise; transient response; Al0.2Ga0.8As; GaAs; III-V semiconductor thin APDs; In0.52Al0.48As; InP; avalanche photodiodes; bandwidth reduction; dead-space effect; excess noise factor; frequency response fluctuations; frequency-response characteristics; gain-bandwidth characteristics; gain-bandwidth product; impact ionization; impulse response autocorrelation function; ionization coefficient history dependence; multiplication-layer width; parallel computer; photocurrent power-spectral density; recurrence technique; thin multiplication layers; ultrafast receivers; Autocorrelation; Avalanche photodiodes; Bandwidth; Concurrent computing; Difference equations; Frequency response; Gallium arsenide; History; Indium phosphide; Ionization;
Journal_Title :
Electron Devices, IEEE Transactions on
