Mechanical stress measurements using micro-Raman spectroscopy

Abstract

The application of micro-Raman spectroscopy for measurements of mechanical stress in silicon microelectronics devices is discussed. The advantages and disadvantages of the technique are shown through different examples such as Si 3 N 4 and metal lines, isolation structures and solder bumps.

Residual stress measurements in polycrystalline graphite with micro-Raman spectroscopy

“…A candid way to relate measured Raman shift to stress magnitude is the use of a stress model illustrating the stress state in the constituents or in the bulk sample within crystallites of arbitrary orientation. A linear relationship between Raman lineshift and stress has been previously applied to estimate the stress values in graphite fibre (Sakata et al, 1988), graphene based mechanical systems (Mohiuddin et al, 2009), quartz (Harker et al, 1970), polycrystalline Mn-Zn ferrite (Yamashita and Ikeda, 2004), polycrystalline silicon (Becker et al, 2007;Wolf and Maes, 1998) etc.…”

“…Micro-Raman spectroscopy is a non-destructive technique and provides information on the microscopic state of stresses in the constituents of materials with up to a micrometre of lateral and depth spatial resolutions (Anastassakis et al, 1970;Wolf and Maes, 1998). The lateral and depth spatial resolution is along the XY and Z directions, respectively and the Z spatial resolution depends on the confocality of the spectroscope used.…”

Fabrication and characterization of uniaxially strained SOI with wafer level by mechanical bending and annealing

“…4 to characterize the strain value. Despite the complexity for the relation between strain or stress and the Raman frequency, 21 it becomes simply linear for uniaxial stress (σ) and strain (ε) in our case according to De Wolf: 16,25,26 FIG. 4.…”

“…Generally, compressive strain will result in an increase of the Raman frequency, and the tensile strain will result in the decrease. 25,27 Herein, ∆ω can be obtained to be 0.44 cm -1 with Raman frequency of 520.88 cm -1 (red line) and 520.44 cm -1 (black dotted line) for the strained and unstrained SOI (Fig. 4), respectively.…”

Novel InP-based optical MEMS device

“…A stress level of 100 MPa would induce a line shift of ϳ0.2 cm −1 in silicon. 19 An argon laser of wavelength 514.5 nm is used in the Raman spectroscopy experiment. A penetration depth of ϳ90 nm for a 514.5 nm wavelength excitation is capable of measuring stresses from a volume of ϳ0.4 m 3 .…”