High-temperature, structural disorder, phase transitions, and piezoelectric properties of GaPO4

Gallium orthophosphate was studied at high temperature up to 1303 K by total neutron scattering and 1173 K by piezoelectric measurements. Rietveld refinements at 1223 K confirm the stability of the structural distortion in the alpha-quartz-type phase with an average tilt angle delta=18.8° at this temperature. In contrast, reverse Monte Carlo (RMC) refinements of total neutron scattering data indicate that, whereas the degree of structural disorder initially slowly varies over a very large temperature interval in the alpha-quartz-type phase, an increase in disorder is observed beginning above 1023 K. Piezoelectric measurements indicate that the quality factor (Q) of GaPO4 resonators remains stable up to this temperature above which the piezoelectric properties of the material degrade. This degradation can be correlated to the increase in structural disorder. RMC refinements indicate that the high-temperature beta-cristobalite-type phase at 1303 K is characterized by significant thermally induced disorder with oxygen atom density forming a continuous ring around the vector joining neighboring gallium and phosphorous atoms. Gallium phosphate may be expected to retain its piezoelectric properties up to within 200 K of the phase transition temperature and as a consequence be used in applications at temperatures slightly above 1000 K.

[1]  P. Hofmann,et al.  Structural Phase Transformations in Crystalline Gallium Orthophosphate , 2000 .

[2]  P. Gille,et al.  High-temperature phase transitions of gallium orthophosphate (GaPO4) , 1999 .

[3]  I. Swainson,et al.  Direct measurement of the Si–O bond length and orientational disorder in the high-temperature phase of cristobalite , 1997 .

[4]  D. Keen.  A comparison of various commonly used correlation functions for describing total scattering , 2001 .

[5]  M. Ghiorso,et al.  Inverted high-temperature quartz , 1979 .

[6]  A. K. Tyagi,et al.  Preparation, phase transition and thermal expansion studies on low-cristobalite type Al1−xGaxPO4 (x=0.0, 0.20, 0.50, 0.80 and 1.00) , 2003 .

[7]  D. Hatch,et al.  The α-β phase transition in cristobalite, SiO2 , 1991 .

[8]  J. Haines,et al.  The effects of pressure, temperature and composition on the crystal structures of α-quartz homeotypes , 2004 .

[9]  D. Keen,et al.  Local structures of amorphous and crystalline phases of silica, SiO2, by neutron total scattering , 1999 .

[10]  K. Kihara,et al.  An X-ray study of the temperature dependence of the quartz structure , 1990 .

[11]  J. Haines,et al.  Piezoelectric characterization and thermal stability of a high-performance α-quartz-type material, gallium arsenate , 2005 .

[12]  A. Goiffon,et al.  A general survey of quartz and quartz-like materials : Packing distortions, temperature, and pressure effects , 1996 .

[13]  J. Haines.  Single-crystal X-ray diffraction study of ?-quartz-type Al1?xGaxPO4 , 2004 .

[14]  I. Gregora,et al.  Raman study of AlPO4 (berlinite) at the α–β transition , 2003 .

[15]  J. Haines,et al.  Crystal structures of α-quartz homeotypes boron phosphate and boron arsenate: structure-property relationships , 2004 .

[16]  B. Dorner,et al.  On the mechanism of the α-β phase transformation of quartz , 1974 .

[17]  J. Haines,et al.  Growth and dielectric characterization of large single crystals of GaAsO4, a novel piezoelectric material , 2003 .

[18]  V. Heine,et al.  Rigid unit modes in framework silicates , 1995, Mineralogical Magazine.

[19]  C. Calvo,et al.  X-ray study of the twinning and phase transformation of phosphocristobalite (AlPO4) , 1977 .

[20]  J. Haines,et al.  The use of composition and high pressure to extend the range of α-quartz isotypes , 2001 .

[21]  H. Arnold,et al.  Die III-V-Analoga des SiO2 , 1980 .

[22]  Martin T. Dove,et al.  Dynamic structural disorder in cristobalite: neutron total scattering measurement and reverse Monte Carlo modelling , 2001 .

[23]  D. Keen,et al.  A detailed structural characterization of quartz on heating through the α−β phase transition , 2001, Mineralogical Magazine.

[24]  Martin T. Dove,et al.  Structural disorder and loss of piezoelectric properties in α-quartz at high temperature , 2002 .

[25]  R. Mcgreevy,et al.  Reverse Monte Carlo modelling , 2001 .

[26]  H. Sowa.  The crystal structure of GaPO4 at high pressure , 1994 .

[27]  Olivier Cambon,et al.  A neutron diffraction study of quartz-type FePO4: high-temperature behavior and α–β phase transition , 2003 .

[28]  Laurent Chapon,et al.  A Neutron Diffraction Study of the Thermal Stability of the α-Quartz-Type Structure in Germanium Dioxide , 2002 .

[29]  Kristian M. Groom,et al.  Comparative study of InGaAs quantum dot lasers with different degrees of dot layer confinement , 2002 .

[30]  R. Roy,et al.  Studies of Silica‐Structure Phases: I, GaPO4, GaAsO4, and GaSbO4 , 1956 .

[31]  D. Hatch,et al.  The α-β phase transition in AlPO4 cristobalite: Symmetry analysis, domain structure and transition dynamics , 1994 .

[32]  G. McIntyre,et al.  Neutron and X-Ray Structure Refinements between 15 and 1073 K of Piezoelectric Gallium Arsenate, GaAsO4: Temperature and Pressure Behavior Compared with Other α-Quartz Materials , 1999 .

[33]  Alain Ibanez,et al.  Structure Deformations and Existence of the α-β Transition in MXO4 Quartz-like Materials , 1994 .

[34]  Y. Muraoka,et al.  The temperature dependence of the crystal structure of berlinite, a quartz-type form of AlPO4 , 1997 .

[35]  Martin T. Dove,et al.  Reverse Monte Carlo modelling of crystalline disorder , 2005 .

[36]  K. Kihara,et al.  The crystal structure of the quartz-type form of GaPO4 and its temperature dependence , 1995 .

[37]  A. Wright,et al.  The structures of the β-cristobalite phases of SiO2 and AlPO4 , 1975 .

[38]  A. Goiffon,et al.  Etude comparée à diverses températures (173, 293 et 373°K) des structures de type quartz α des phases MIIIXVO4 (MIII = Al, Ga et XV = P, As) , 1986 .

[39]  Alex C. Hannon,et al.  Results on disordered materials from the GEneral Materials diffractometer, GEM, at ISIS ☆ , 2005 .