Title :
Quantum Well Saturation Effect on the Reduction of Base Transit Time in Light-Emitting Transistors
Author :
Hsiao-Lun Wang ; Hao-Hsiang Yang ; Chao-Hsin Wu
Author_Institution :
Grad. Inst. of Photonics & Optoelectron., Nat. Taiwan Univ., Taipei, Taiwan
Abstract :
In this paper, we demonstrate the improvement of cutoff frequency of the light-emitting transistor (LET) due to quantum well (QW) band-filling phenomenon (i.e., saturation) along with the carrier capturing and escaping processes in the base region. Through microwave measurement followed by small-signal model analysis, we observe that the base transit time, τt, of the LET is reduced evidently from 90 to 20 ps when the collector current density increases from 2.43 to 34.9 kA/cm2. The reduction of τt via saturation effect can be explained by the electroluminescence spectrum and thermionic emission theory of QW.
Keywords :
light emitting devices; semiconductor quantum wells; transistors; LET; QW band-filling phenomenon; base transit time reduction; carrier capturing processes; collector current density; cutoff frequency; electroluminescence spectrum; escaping processes; light-emitting transistors; microwave measurement; quantum well saturation effect; saturation effect; small-signal model analysis; thermionic emission theory; Current density; Gallium arsenide; Heterojunction bipolar transistors; High-speed optical techniques; Optical saturation; Quantum well lasers; Carrier capture and escape time; light-emitting transistor (LET); quantum well (QW) saturation;
Journal_Title :
Electron Devices, IEEE Transactions on
DOI :
10.1109/TED.2014.2349922
