Titanium is a promising new material system for the bulk micromachining of microelectromechanical ͑MEMS͒ devices. Titaniumbased MEMS have the potential to be used for a number of applications, including those which require high fracture toughness or biocompatibility. The bulk titanium etch rate, TiO 2 mask etch rate, and surface roughness in an inductively coupled plasma ͑ICP͒ as a function of various process parameters are presented. Optimized conditions are then used to develop the titanium ICP deep etch ͑TIDE͒ process. The TIDE process is capable of producing high aspect ratio structures with smooth sidewalls at etch rates in excess of 2 m/min, providing a new means for the microfabrication of titanium-based MEMS devices.

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The influence of hydrogen plasma treatment before atomic layer deposition of aluminum oxide on In 0:53 Ga 0:47 As is investigated. Experiments on untreated, trimethylaluminum-treated, hydrogen-plasma treated, and iterative hydrogen plasma/trimethylaluminum-treated samples are compared in the context of interface trap density, D it . Through the conductance method, it was found that five cycles of two s, 20 mT, 100 W hydrogen plasma alternating with 40 msS of trimethylaluminum dose prior to dielectric growth resulted in a reduction of interface trap density (0.2 eV below the conduction band edge) from 4:6 Â 10 12 eV À1 cm À2 for untreated samples to 1:7 Â 10 12 eV À1 cm À2 for treated samples.

We report Al 2 O 3 /In 0.53 Ga 0.47 As MOSFETs having both self-aligned in situ Mo source/drain ohmic contacts and self-aligned InAs source/drain n + regions formed by MBE regrowth. The device epitaxial dimensions are small, as is required for 22-nm gate length MOSFETs; a 5-nm In 0.53 Ga 0.47 As channel with an In 0.48 Al 0.52 As back confinement layer and the n ++ source/drain junctions do not extend below the 5-nm channel. A device with 200-nm gate length showed I D = 0.95 mA/μm current density at V GS = 4.0 V and g m = 0.45 mS/μm peak transconductance at V DS = 2.0 V. Index Terms-InAs source/drain, InGaAs MOSFET, migration-enhanced epitaxial regrowth, source/drain regrowth, III-V MOSFET.

A nanofabricated laser desorption ionization mass spectrometry (LDI-MS) chip for quantitation of small molecules.

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We report on a technique of grading the heterobarrier interfaces of a p-type distributed Bragg reflector mirror to reduce the operating voltages of vertical-cavity surface-emitting lasers (VCSELs). We report VCSELs with lower operating voltages (2–3 V) and record continuous-wave room-temperature power-conversion efficiencies (17.3%). We experimentally demonstrate that by using a parabolic grading and modulating the doping correctly, a flat valence band is generated that provides low voltage hole transport. The low resistance mirrors are achieved using low Be doping, digital-alloy grading and 600 °C growth temperatures.