Inductively coupled plasma (ICP) dry etching rendered structural and electrical enhancements on type-II antimonide-based superlattices compared to those delineated by electron cyclotron resonance (ECR) with a regenerative chemical wet etch. The surface resistivity of 4 X 10~(5) OMEGA cm is evidence of the surface quality achieved with ICP etching and polyimide passivation. By only modifying the etching technique in the fabrication steps, the ICP-etched devices with a 9.3 (mu)m cutoff wavelength revealed a diffusion-limited dark current density of 4.1 X 10~(-6) A/cm~(2) and a maximum differential resistance at zero bias in excess of 5300 OMEGA cm~(2) at 77 K, which are an order of magnitude better in comparison to the ECR-etched devices.
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