One of the strategies to overcome the limits of classical dimensional scaling in semiconductor technology is the use of III-V compound semiconductors as a high-mobility channel material for performance optimization of the eventual device. The growth of these alloys on industry-standard Si wafers is challenging and may lead to the introduction of defects and compositional fluctuations. At the same time, engineering of the charge transport requires control over doping concentrations and distributions. Accurate measurements of these properties are particularly difficult given the high surface-to-volume ratio of the structures and the large lattice mismatches with the substrate. In this topic, the use and optimization of micro-Raman spectroscopy is investigated for measuring the local properties in next-generation semiconductor architectures. Raman spectra for III-V materials are in general quite complex and the small dimensions of the region of interest further complicate the measurement. However, it was recently found that a nano-focusing phenomenon enables the confinement of the excitation light inside the structures, leading to considerable enhancement of the Raman response. The internship will involve experimental work on state-of-the-art transistor structures combined with the development of a thorough understanding of the III-V Raman coupled modes. The resulting measurements will be correlated with complementary metrology but the experimental work focuses on the Raman spectroscopy. The student will learn to work with a micro-Raman system using different laser wavelengths. A strong physics background is required. The student will be trained in working with a Raman system and characterize advanced semiconductor device structures. He/she will be part of the materials and component analysis (MCA) department.
Type of project: Internship, Thesis, Combination of internship and thesis
Duration: 6 months
Required degree: Master of Science, Master of Engineering Science
Required background: Materials Engineering, Nanoscience & Nanotechnology, Physics
Supervising scientist(s): For further information or for application, please contact: Thomas Nuytten (Thomas.Nuytten@imec.be)
Imec allowance will be provided.