The contributions of the acoustic modes and optical modes to the primary pyroelectric coefficient of GaN

As competitive next generation pyroelectric sensors, the pyroelectricity of GaN has been investigated. The specific heat of the wurtzite GaN is calculated from the Raman-scattering data. The contributions of the acoustic modes and optical modes to the primary pyroelectric coefficient of GaN are calculated from 0 to 600 K. An explicit expression of the primary pyroelectric coefficient as a function of temperature is derived. It is found that the primary pyroelectric coefficient of GaN can be expressed as the sum of the Debye function and Einstein function. It is substantially different from that of conventional ferroelectrics-based pyroelectric devices which can be described only by the Einstein function.

[1]  D. Sedmidubský,et al.  Calculation of the thermodynamic properties of AIII nitrides , 2006 .

[2]  N. H. March,et al.  A model pyroelectric: Properties by computer simulation , 1981 .

[3]  Stefan K. Estreicher,et al.  Heat capacity of α-GaN : Isotope effects , 2005 .

[4]  M. Shur,et al.  Pyroelectricity in gallium nitride thin films , 1996 .

[5]  R. Davis,et al.  Phonon density of states of bulk gallium nitride , 1998 .

[6]  K. Matocha,et al.  Comparison of metal-oxide-semiconductor capacitors on c- and m-plane gallium nitride , 2007 .

[7]  Paul Muralt,et al.  Properties of aluminum nitride thin films for piezoelectric transducers and microwave filter applications , 1999 .

[8]  K. Y. Tong,et al.  Numerical simulation of current–voltage characteristics of AlGaN/GaN HEMTs at high temperatures , 2005 .

[9]  Andrei Osinsky,et al.  Pyroelectric properties of AlN , 2000 .

[10]  F. Bernardini,et al.  Accurate calculation of polarization-related quantities in semiconductors , 2001 .

[11]  E. Maksimov,et al.  The low-temperature behaviour of the pyroelectric coefficient , 1989 .

[12]  M. Born,et al.  Dynamical Theory of Crystal Lattices , 1954 .

[13]  David Vanderbilt,et al.  Spontaneous polarization and piezoelectric constants of III-V nitrides , 1997 .

[14]  P. Han,et al.  Temperature dependence of the pyroelectric coefficient and the spontaneous polarization of AlN , 2007 .

[15]  B. Szigeti.  Temperature Dependence of Pyroelectricity , 1975 .

[16]  N. D. Gavrilova,et al.  Low-temperature pyroelectricity , 2000 .

[17]  A. N. Smirnov,et al.  Phonon dispersion and Raman scattering in hexagonal GaN and AlN , 1998 .

[18]  E. Ejder.  Refractive Index of GaN , 1971, August 16.