Shubnikov-de Haas measurements of the 2-D electron gas in pseudomorphic In0.1Ga0.9As grown on GaAs

✍ Scribed by P.P. Szydlik; S.A. Alterovitz; E.J. Haugland; B. Segall; T.S. Henderson; J. Klem; H. Morkoc

• Book ID: 103917782
• Publisher: Elsevier Science
• Year: 1988
• Tongue: English
• Weight: 281 KB
• Volume: 4
• Category: Article
• ISSN: 0749-6036
• DOI: 10.1016/0749-6036(88)90248-0

✦ Synopsis

Shubnikov-de

Haas (SdH) measurements were performed on a 200 A laver of pseudomorphic InD.lDGaD.gDAs grown by molecular beam epitaxy on undoped GaAs with an overlayer of A10.15GaO.85As.

The AlGaAs consists of a spacer and a heavily doped layer.

Measurements were taken in magnetic fields up to 1.4 tesla in the temperature range 1.4K < T < 10K.

Analysis of the SdH data indicated that only one sub-band was populated with a density of 5.8x1011cm-2 and an effective mass at the Fermi level m*= (0.060 +.OO1)mn.

No maanetic field dependence of m* was observed.

Hall effect -measurzments in-this temperature range gave a Hall mobility HH= 9.1x104 cm2/Vs.

The transport scattering time (derived from HH)rH =3.lps and the SdH derived scattering time TSdH =0.55pS yield a ratio TH/TSdH-6.

This ratio is intermediate between the ratio of approximately unity found in Si MOSFETs and values of order lo-40 found in AlGaAslGaAs heterostructures.

The ratio, and the two separate characteristic times observed in our sample, can be explained in terms of the dominance of alloy and ionized impurity scattering at low temperatures.