Cr/- and Fe/n-GaAs Schottky diodes: the stable current-voltage characteristic produced by high-temperature annealing

摘要

The electrical characteristics of Cr/- and Fe/liquid-encapsulatedCzochralski - (LEC)n-GaAs Schottky barrier diodes (SBDs) annealed attemperatures from 100 to 300 ℃ for 5 min and from 350 to 800 ℃ for1 min have been investigated as a function of annealing temperature,with the use of current-voltage (I-V) techniques. For Cr/n-GaAs SBDs,the Schottky barrier height Φ_b and ideality factor n values rangefrom 0.57 eV and 1.10 (for the as-deposited sample) to 0.80 eV and1.10 (for 650 ℃ annealing). The ideality factor values remainapproximately unchanged up to 650 ℃ and increased to l.28 at 700 ℃(Φ_b = 0.81 eV). For Fe/n-GaAs SBDs, the Φ_b and n values rangefrom 0.60 eV and 1.06 (for the as-deposited sample) to 0.78 eV and 1.08 (for 400 ℃ annealing). After 400 ℃ annealing, while the nvalues of the Fe/n-GaAs SBDs remain approximately unchanged between1.10 and 1.12 up to 650 ℃ annealing, the Φ_b value decreased withincreasing temperature and became 0.75 at 650 ℃ (n = 1.11) and 0.73at 700 ℃ (n = 1.20). It has been seen that the Cr/- and Fe/LECn-GaAscontacts are thermally stable under annealing up to 650 ℃.