Techniques to minimize DX center deleterious effects in III-V device performance

Abstract

The properties of deep donor states (DX centers) in III-V alloys are discussed in relation to their influence on device characteristics and performance. The techniques to avoid or minimize such deleterious effects in AlGaAs-based devices are discussed, along with their physical basis, and some guidelines for improved III-V device design are established. New results about the benefits of proper donor selection, the role of In alloying, the advantage of δ doping in layers and in modulation-doped devices, and the use of AlInAs and InGaP as alternative wide band-gap III-V alloys are presented.

Optimization of the growth of the InGaP etch-stop layer by MOVPE for InGaP/GaAs HBT device application

“…It suggests that the As atoms can easily replace P atoms on the InGaP surface at high temperature when the sample was exposed to the As vapor during the gas-switching period. That is, the In x Ga 1Àx As y P 1Ày intermixing layer was easier to form at higher temperature growth [6][7][8][9][10][11][12]. In this work, the optimized growth temperature of the GaAs cap layer was 575 1C, because the As/P exchange on the surface was well suppressed at this temperature.…”

Low-noise GaAs quantum dots for quantum photonics

“…Such a structure is missing for GaAs QDs 13 , 16 , 22 – 25 —in previous attempts, charge-stability was not demonstrated 31 , 32 . A materials issue must be addressed: the barrier material AlGaAs must be doped, yet silicon-doped AlGaAs contains DX-centres 33 , 34 which both reduce the electron concentration, causing the material to freeze out at low temperatures, and lead to complicated behaviour under illumination. Here, we resolve this issue—all doped AlGaAs layers have a low Al-concentration.…”

Electrical transport properties of silicon delta-doped Al0.30Ga0.70As samples showing suppression of the DX center features

“…The growth interruption just before and after deposition of the silicon atoms was, in an introductory way, considered by Muñoz et al 33 They reported a reduction of the relative silicon concentration acting as the DX center by introducing a 15 s growth interruption. We used a 1 min interruption, so that it might play a role in lowering the concentration of the DX center.…”