Stress Analysis for Semiconductor Raw Materials

Emerging display technologies demand high brightness, low power consumption and longer lifetime. Arrays, of self-emitting, micron-sized LEDs or Micro-LED (µLED), are considered a strong contender to replace current OLED or LCD displays.

Raman spectroscopy is a very well suited technique to determine both Ge fraction and strain in SiGe layers and Si cap layers. Moreover the possibility of using both UV and visible excitation lines on the same instrument is essential to study structures made up of a Silicon cap layer on top of a SiGe layer. The relative Ge content in the constant Si1-xGex layer is calculated from the visible Raman spectrum and the strain of the cap Si layer is derived from the UV Raman spectrum.

In this application note, Raman spectroscopy is explored as an easier and more flexible technique for quantifying common components in a CMP slurry, such as benzotriazole and glycine, without any sample preparation or costly consumables.

We have performed a complete Raman polarized study of a single GaN nanowire using a confocal microscope together with a high resolution stage. The high spatial resolution of our Raman confocal instrument together with a piezoelectric stage demonstrates unambiguously the possibility to image the optical properties of nano-objects with a resolution better than 200 nm keeping the fill advantage of the polarization control under a confocal microscope.