Micro-Raman probing of residual stress in freestanding GaN-based micromechanical structures fabricated by a dry release technique

作者：Tripathy S^*; Lin Vivian K X; Vicknesh S; Chua S J

来源：Journal of Applied Physics, 2007, 101(6): 063525.

DOI：10.1063/1.2713089

In this study, the authors have employed micro-Raman scattering to characterize the residual stress in freestanding GaN-based micromechanical structures on (111)-oriented silicon substrates. Arrays of freestanding cantilevers and microbridges have been fabricated using a combination of dry etching techniques. The Si material beneath the GaN microstructures is removed by a nonplasma XeF2-based dry release technique. Two distinct sets of GaN-based layers on Si(111) with a different amount of growth-induced tensile stress are selected for the fabrication of freestanding cantilevers. The residual stress in these micromechanical structures is determined from the peak shift of the E-2-high phonon mode of GaN. Such GaN mechanical structures on Si platforms may be useful for the fabrication of GaN-based microelectromechanical systems and sensors.

• 出版日期2007-3-15