Study of High-Spatial Resolution Strain Measurements in Semiconductor Devices Using Tip-Enhanced Raman Spectroscopy

将拉曼光谱与原子力显微镜（AFM）相结合，实现了尖端增强拉曼光谱（TERS）。远场信号（背景）频繁地干扰我们从得到的光谱中推导出TERS信号。为了抑制背景，我们详细地研究了背景和信号的极化特性。因此，在入射光和散射光分别为p偏振和s偏振的条件下，[110]获得了高强度的TERS信号与背景的比。通过将实验结果与基于尖端增强模型的计算结果与“尖端放大张量”进行比较，得到了约1.6〓105的增强因子。获得的增强因子值高于先前报道的约104。在剪切力AFM测量中，高增强因子的原因被认为是在样品表面附近留有尖端。

Tip-enhanced Raman spectroscopy (TERS) was realized by combining Raman spectroscopy and atomic force microscopy (AFM). Far-field signal (background) frequently interrupts us to derive the TERS signal from obtained spectra. To suppress the background, the polarization properties of both TERS signal and background were examined in detail. As a result, high-intensity ratio of the TERS signal to background was obtained in the conditions of [110] incidence and p and s polarizations of the incident and scattered lights, respectively. Anenhancement factor of approximately 1.6 〓 105 was obtained by comparing the experimental results and calculations based on the tip-enhanced modeling with the “tip-amplification tensor.” The obtained value of the enhancement factor was higher than the previously reported value of about104. The reason for the high enhancement factor is considered to be the tip apex remaining in the vicinity of the sample surface in the shear-force AFM measurements.