Super-Resolution Raman Spectroscopy by Digital Image Processing

Abstract EN

We demonstrate the results of a strain (stress) evaluation obtained from Raman spectroscopy measurements with the super-resolution method (the so-called super-resolution Raman spectroscopy) for a Si substrate with a patterned SiN film (serving as a strained Si sample).

To improve the spatial resolution of Raman spectroscopy, we used the super-resolution method and a high-numerical-aperture immersion lens.

Additionally, we estimated the spatial resolution by an edge force model (EFM) calculation.

One- and two-dimensional stress distributions in the Si substrate with the patterned SiN film were obtained by super-resolution Raman spectroscopy.

The results from both super-resolution Raman spectroscopy and the EFM calculation were compared and were found to correlate well.

The best spatial resolution, 70 nm, was achieved by super-resolution Raman measurements with an oil immersion lens.

We conclude that super-resolution Raman spectroscopy is a useful method for evaluating stress in miniaturized state-of-the-art transistors, and we believe that the super-resolution method will soon be a requisite technique.