MSE Seminar Series: Metrology for Advanced Transistor Devices and Materials
Friday, February 19, 2021
Title: Metrology for Advanced Transistor Devices and Materials
Speaker: Alan Diebold, Empire Innovation Professor of Nanocscale Science, SUNY Polytechnic Institute
In this talk, we discuss the measurement of materials and device structures critical to the next generation of integrated circuits. Specifically, this presentation will cover measurements for new dielectric materials and nanowire/nanosheet transistors known as Gate – all – Around (GAA) transistors. As transistor dimensions shrink, the dielectric layer in the transistor gate must evolve to increase its dielectric constant. This is typically done by changing the crystal phase of so called High - K dielectric layers. The X-ray methods used to determine the phase of the material will be presented. Another difficult measurement challenges is non-destructively determining the feature dimensions and shape for complicated 3D structures. This presentation will review Mueller Matrix Spectroscopic Ellipsometry based scatterometry which uses the Rigorous Coupled Wave Approximation (RCWA) to solve Maxwell’s equations for a model structure and the resulting Mueller Matrix elements are compared to experimental results. Here we measured and characterized test structures used to develop etch process for the GAA transistors. We also discuss experimental measurement of nanowire test structures using critical dimension small angle X-ray scattering. This new method is being explored as a means of measuring feature dimensions for the most advanced transistor and memory circuits.