Characterisation of Multiple Carrier Transport in Indium Nitride Grown by Molecular Beam Epitaxy

Abstract

Transport properties of two distinct electron species in indium nitride grown by molecular beam epitaxy (MBE) have been measured. Variable field Hall and resisitivity voltages were used in a quantitative mobility spectrum analysis (QMSA) to extract the concentrations and mobilities of the two electron species, attributed to the bulk electrons and a surface accumulation layer. Single magnetic field data corresponds to neither electron species. The bulk electron distribution has an extracted average mobility of 3570 cm 2 /(V s) at 300 K, which rises to over 5100 cm 2 /(V s) at 150 K. Bulk electron concentration in the sample is 1:5 Â 10 17 cm À3 . The surface electrons have a higher sheet charge density and an order of magnitude lower average mobility than those in the bulk.

Multiple carrier transport in N‐face indium nitride

“…1b) increases rapidly with temperature until around 100 K, and peaks around 150 K, before decreasing more slowly. The peak electron mobility for the 2 µm thick sample is over 3000 cm 2 /V s. The mobility in this material is not as high that seen in In-polar material, which peaks over 5100 cm 2 /V s [7], even though the bulk concentration is lower. The mobility of all samples at 300 K is greater than at 20 K. This is in contrast to In-polar InN in which the bulk mobility is generally symmetric around 150 K with mobilities at 20 K and 300 K being of a similar value [7,14].…”

“…The peak electron mobility for the 2 µm thick sample is over 3000 cm 2 /V s. The mobility in this material is not as high that seen in In-polar material, which peaks over 5100 cm 2 /V s [7], even though the bulk concentration is lower. The mobility of all samples at 300 K is greater than at 20 K. This is in contrast to In-polar InN in which the bulk mobility is generally symmetric around 150 K with mobilities at 20 K and 300 K being of a similar value [7,14]. The extracted mobility of the bulk electrons increases with sample thickness, which, as for the decrease in electron density, is considered to be largely due to an improvement in crystal quality away from the growth interface.…”

“…To measure the transport properties (concentration, mobility) of both electron species, variable magnetic field Hall and resistivity measurements with multi-carrier analysis techniques have been used successfully [6,7]. To date, however, published results using multiple carrier analysis are for In-polar InN [7] or films of unspecified polarity [6].…”

Electrical and optical properties of p-type InN

“…It has been shown previously that charge transport in n-type InN is well described by a model with two perfectly electrically connected layers: the SEAL and the n-type bulk layer 8,13 .…”

Erratum: Characterisation of multiple carrier transport in indium nitride grown by molecular beam epitaxy [Phys. Status Solidi C 4, 2423–2427 (2007)]

“…The following sentence should be appended after the last sentence of the introduction: "These results were briefly reported recently [10], with the measurement and analysis techniques, and discussed in more detail in this paper. "…”