Semiconductor Photoemissive Structures for Far Infrared Detection

Terahertz absorption in AlGaAs films and detection using heterojunctions

“…Reflection losses could be reduced by employing methods such as antireflection coatings for the desired wavelength ranges. These results for Al x Ga 1Àx As with x = 0.01 are similar to those for doped GaAs [11]. As the Al fraction is increased the absorption will decrease, with a 10-20% decrease in absorption at x = 0.20 as shown in Fig.…”

“…1(a). In the standard HEIWIP design, D b < 1 meV (for 1 · 10 15 cm À3 residual doping) and can be ignored, D d $ 9-10 meV [11] (for 1À8 · 10 18 cm À3 ), and D x = 530x meV based on 35% offset in the valence band. As x is decreased k 0 increases, however due to D d there is a limit of k 0 $ 110 lm associated with the MBE growth limit for the lowest Al fraction (x = 0.005).…”

Infrared detectors: an overview

“…Various semiconductor photoemissive structures for far IR detection have been discussed by Perera [32].…”

Terahertz Detection Devices

“…Since then, several different types of internal photoemission detectors have been demonstrated (Shepherd, 1992;Perera et al, 1995;Perera, 2001). Among the most important types are metal-semiconductor Schottky barrier IR detectors, such as PtSi/Si detectors (Kosonocky, 1992) operating in 3-5 mm; semiconductor heterojunction IR detectors, such as Ge x Si 1Àx /Si detectors [Lin and Maserjian (1990), Tsaur et al, (1991)] developed for 8-14 mm or even longer wavelengths; and a degenerate Si homojunction detector [Tohyama et al (1991)], which has a response in the 1-7 mm range.…”