Fundamental Material Study of GeSn for Si Photonics Application
Abstract
Silicon, Germanium and their alloys have been the miracle materials for the electronics industry that drive the digital revolution. The rapid ÒMooreÕs lawÓ miniaturization of device sizes has yielded an ever-increasing density of fast components integrated on Si, pushing down feature size close to its ultimate physical limits. At the same time, there has been a parallel effort to broaden the reach of the materials by expanding its functionalities well beyond electronics evidenced by the development of Group-IV photonics. By simply introducing the next group-IV element ÒTinÓ (Sn), a new material platform GeSn could be created with tremendous new electrical, optical, and mechanical properties which could dramatically change the landscape of future microelectronics/photonics. For the past decade, studies on GeSn show a large discrepancy of the results among research groups worldwide, which is mainly due to the inaccurately used material parameters such as bowing factors. Therefore, the fundamental material characteristics are needed to be revisited to be able to provide accurate information for future device design. The goal of this project is to conduct a deepened systematic study of GeSn material system via investigation of fundamental material characteristics to establish a complete database, which could provide sufficient design information for GeSn-based device development. This goal is to be accomplished by leveraging the systematic material and optical characterizations and extracting the bowing factors for accurate calculations, as described in followings: i) The Sn composition will be identified independently using X-ray Diffraction (XRD), Rutherford backscattering spectrometry (RBS), secondary ion mass spectrometry (SIMS), atomic probe tomography (APT) and X-ray photoelectron spectroscopy (XPS) techniques with cross check to make the results more accurate; ii) The bowing factor for lattice constant will be considered in the very beginning. By using XRD reciprocal space map (RSM) technique at temperatures from 300 to 10 K, the lattice constant and strain of the material will be precisely measured at each temperature. Based on the identified Sn composition, lattice constant and strain, the bowing factor can be obtained via data fitting process; iii) Using optical characterization techniques such as photoluminescence excitation (PLE), modulation spectroscopy and ellipsometry spectroscopy to investigate the bandgap energies. Extracting the bowing factors (different from the one for lattice constant) for bandgap energies.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Mar 18, 2019
- Source ID
- W911NF1910004
Entities
People
- Mansour Mortazavi
Organizations
- Army Contracting Command
- Office of the Secretary of Defense
- University of Arkansas at Pine Bluff