Effect of impurity trapping on the capacitance-voltage characteristics of n-GaAs/N-AlGaAs heterojunctions

Journal Article · Mon Feb 10 00:00:00 EST 1986 · Appl. Phys. Lett.; (United States)

DOI:https://doi.org/10.1063/1.96520· OSTI ID:6047570

Tan, K L; Lundstrom, M S; Melloch, M R

We have studied the capacitance-voltage (C-V) characteristics of Schottky barriers on inverted n-GaAs/N-AlGaAs and normal N-AlGaAs/n-GaAs heterojunctions. Impurities introduced during film growth produced a negative sheet charge of 6.0 x 10 cm S at the interface of the inverted n-GaAs/N-AlGaAs heterojunction. The effectiveness of GaAs quantum wells in trapping these impurities was investigated. GaAs quantum wells 20 A wide were placed in intervals of 2500 A for the first 0.75 m of the AlGaAs layer; in the last 0.25 m, the periodicity of the quantum wells was progressively decreased by half with the last quantum well placed at about 160 A from the GaAs/AlGaAs interface. The resulting measured interface charge concentration of 4.4 x 10 cm S is more than a magnitude lower than measured before the use of the quantum wells and is essentially at the limit of the accuracy of the C-V technique for this structure.

• Research Organization: School of Electrical Engineering, Purdue University, West Lafayette, Indiana 47907
• OSTI ID: 6047570
• Journal Information: Appl. Phys. Lett.; (United States), Vol. 48:6
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM ARSENIDES
ELECTRIC CONDUCTIVITY
HETEROJUNCTIONS
IMPURITIES
TRAPPING
GALLIUM ARSENIDES
CARRIER DENSITY
CHARGE DENSITY
SCHOTTKY BARRIER DIODES
THIN FILMS
ALUMINIUM COMPOUNDS
ARSENIC COMPOUNDS
ARSENIDES
ELECTRICAL PROPERTIES
FILMS
GALLIUM COMPOUNDS
JUNCTIONS
PHYSICAL PROPERTIES
PNICTIDES
SEMICONDUCTOR DEVICES
SEMICONDUCTOR DIODES
SEMICONDUCTOR JUNCTIONS
360603* - Materials- Properties