Research & development - Leuven | More than two weeks ago
Doping means the introduction of impurities into a semiconductor crystal to modify the conductivity. Boron and Phosphorus are the two most important materials used in the semiconductor industry. The doping levels of silicon traditionally are characterized via secondary ion mass spectroscopy (SIMS). However, SIMS yields relative doping levels, and thus relies on the availability of a standard reference material (RM). A widely accepted and commercially available qualified standard reference material for Boron in Si has been established at NIST. However, no absolute standards do exist for Boron doping in other matrices that are gaining importance in the nano-electronics industry, for example SiGe alloys.
Rutherford backscattering spectrometry (RBS) is recognized as a method to determine the absolute concentration without relying on reference standards. In other words, RBS can qualify the necessary reference standards for other techniques, provided that it has the necessary sensitivity. Unfortunately, RBS measurements on standard Silicon substrates do not allow to reach the necessary sensitivity, mainly due to signal interference between Boron and the substrate.
To enable the accurate Boron quantification via RBS, we propose a novel measurement approach on an ultrathin film and in a transmission mode. Such a reference-free technique has been recently developed at imec for pellicles and thin foils, which can be also applied to thin films and devices by the proper specimen preparation. You will push the boundaries of sensitivity by innovations, you will investigate the limit of detection, and you will study possible sources of uncertainty. You will learn to use and interpret various materials characterization techniques that are used in the nano-electronics industry, and understand their strengths, weaknesses, and complementarity. You will be part of a team to develop a method to qualify reference standards. You will establish a reference standard that will be used in the nanoelectronics research and industry for many years to come.
Type of project: Combination of internship and thesis
Duration: 6 - 12 months
Required degree: Master of Science, Master of Engineering Science
Required background: Physics, Nanoscience & Nanotechnology
Imec allowance will be provided for students studying at a non-Belgian university.