Electron transport in In-rich in _xGa _1-xN films

We have performed electrical transport measurements on metal-organic vapor phase epitaxy grown In-rich In _xGa _1-xN (x= 1, 0.98, and 0.92) films. Within the experimental error, the electron density in InGaN films is temperature independent over a wide temperature range (4 K ≤ T ≤ 285 K). Therefore, In _xGa _1-xN (0.92 ≤ x ≤ 1) films can be regarded as degenerate semiconductor systems. The experimental results demonstrate that electron transport in In-rich In _xGa _1-xN (x=l, 0.98, and 0.92) films is metalliclike. This is supported by the temperature dependence of the density, resistivity, and mobility which is similar to that of a metal. We suggest that over the whole measuring temperature range residue imperfection scattering limits the electron mobility in In-rich In _xGa _1-xN (x=1, 0.98, and 0.92) films.