Publications by April S. Brown.

Papers Published

  1. Delaney, M.J. and Brown, A.S. and Mishra, U.K. and Chou, C.S. and Larson, L.E. and Nguyen, L. and Jensen, J., Low temperature MBE growth of GaAs and AlInAs for high speed devices (1989), pp. 64 - 72 [CORNEL.1989.79822] .
    (last updated on 2007/04/14)

    Abstract:
    Low-temperature GaAs buffer technology was used to fabricate high-performance 0.2-μm-gate-length, spike-doped GaAs MESFETs. A 400.0-nm low-temperature GaAs buffer was grown by molecular beam epitaxy (MBE) at a substrate temperature of 300°C. The substrate temperature was raised to 580°C for a brief in situ anneal and followed by the growth of the active spike-doped GaAs MESFET structure. The peak extrinsic transconductance, gm, was 600 mS/mm with an average pinch-off voltage, Vpo, of -0.6 V. An output conductance, go, of 24 mS/mm resulted in a voltage gain of 25. The extrapolated fT of the devices was 79 GHz. Static SCFL (source-coupled FET logic) frequency dividers fabricated in this technology exhibit a maximum clock rate of 22 GHz. Low-temperature AlInAs buffer growth has been applied to GaInAs/AlInAs HEMT (high-electron-mobility transistor devices on InP. A 250.0-nm AlInAs buffer was grown at a substrate temperature of 150°C, followed by an anneal under arsenic overpressure and a GaInAs/AlInAs superlattice prior to the HEMT structure, which is grown at T = 510°C. Devices fabricated with 0.2-μm gates had gm of 670 mS/mm and go of 2.55 mS/mm, giving a voltage gain of 250.

    Keywords:
    Transistors, Field Effect--Fabrication;Molecular Beam Epitaxy;Semiconducting Gallium Arsenide--Growth;