Industrial Applications of Ultrafast Lasers I: Basic Physics and Examples

CU Boulder · JILA X317 | UC Berkeley · Birge 468 Critical to the design and development of present and future semiconductor and quantum devices is the full understanding of the electronic structure of the materials that comprise the complex functional stacks in a non-destructive way. In Seminars I and II, I will describe the application of femtosecond ultraviolet photoelectron and photovoltage spectroscopy (fs UPPS) to fully characterize the electronic structure of industrially important materials and devices. The addition of fs photovoltage spectroscopy, which extracts the underlying semiconductor substrate band bending provides virtually complete characterization of the electronic structure of complex device material stacks. This includes Fermi level location, valence band locations and offsets, oxide properties and charging as a function of processing, and tunnel barrier heights to name a few. In the first seminar I will describe the methodology and physics of this spectroscopic approach. In the Seminar II, I will describe specific material and device studies of key industrial interest; these include high-K/ metal gate MOS devices, earth abundant thin film photovoltaics, the Al2 O3 tunnel barrier utilized in quantum computing transmons, organic LEDs and phase change materials for neuromorphic/AI applications. Additional seminars, if interested would include further examples (earlier studies of electron dynamics at surfaces and interfaces) and femtosecond ablative photomask repair..