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

Volume

61

Issue

10

fYear

2014

fDate

Oct. 2014

Firstpage

3472

Lastpage

3476

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, τ_t, 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 τ_t 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;

fLanguage

English

Journal_Title

Electron Devices, IEEE Transactions on

Publisher

ieee

ISSN

0018-9383

Type

jour

DOI

10.1109/TED.2014.2349922

Filename

6895255