Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 60 (1992), S. 1459-1461 
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: With the objective of developing an improved process for in situ etching of GaAs-based materials in organometallic vapor phase epitaxy reactors, GaAs wafers and AlxGa1−xAs epilayers have been etched with CH3I vapor in a horizontal reactor operated at atmospheric pressure with H2 or He carrier gas. For a H2 flow rate of 2.1 s lpm, etching temperatures from 400 to 625 °C, and CH3I mol fractions (yCH3I)from 0.0012 to 0.015, the measured GaAs etch rate r (in A(ring) min−1) is given by r = k0 y0.83CH3I exp[ − 45(kcal mol−1)/RT] with k0=3.2×1016 A(ring) min−1. The value of k0 depends on the type of carrier gas, flow rate, total pressure, and reactor geometry. The etch rate appears to be controlled mainly by the decomposition of CH3I to CH3 and I, for which the activation energy has been reported to be 43.5 kcal mol−1. The etch rate of AlxGa1−xAs epilayers with x up to 0.7, which was measured at 480 °C with yCH3I= 0.015, does not depend on Al content. The surface morphology of etched GaAs wafers improves with decreasing temperature. Specular surfaces are maintained at temperatures below 500 °C for etch depths up to 5000 A(ring).
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1089-7666
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Heat transfer measurements from thin filaments to argon gas in cells of cylindrical symmetry are made under extreme clean surface conditions so that known constant values of α, the thermal accommodation coefficient, on the filament pertain over the full range of pressures, 0.01–40 Torr. The results are used in an attempt to assess merit of principal theoretical treatments of heat transfer in the transition regime by extracting α according to each treatment and comparing results with the presumed known value. Before relative merit of the theories can be assigned with confidence, a wider differentiation in the α values obtained is needed. It is expected that this may result when similar experiments for the higher α gases, krypton and xenon, can be completed and critically examined.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...