A
Raman scattering method for measuring a GaN
thermal expansion coefficient includes the following steps that 1, a sample is scribed, sampled and cleaned; 2, variable-temperature Raman testing is performed on the sample; 3,
linear fitting is performed on a testing result, and the
linear fitting slope and intercept are extracted. According to the extracting result, the
thermal expansion behavior of a
solid material is tested and represented in combination with the physical meaning of Gruneisen parameters. The variable-temperature
Raman scattering technology is adopted,
Raman scattering is utilized for obtaining the relation between Raman
phonon frequency shift and temperature,
nondestructive testing and representing can be accurately performed on
thermal expansion behaviors of epitaxial layer film two-element and multi-element
alloy systems of GaN, AlN, InN and other III group nitrides, and therefore it is avoided that in a common representation method, the sample is damaged, and formula derivation and mathematical calculation are complex; because no strict requirements for the shape and size of the sample exist, the thermal expansion behaviors of all kinds of
semiconductor materials can be conveniently tested, and the method is simple, easy to implement and small in error.