Buried Layer Low Gain Avalanche Diodes. Issue 1 (1st November 2022)

• Record Type: Journal Article
• Authors: Apresyan, A.; Giacomini, G.; Heller, R.; Mannelli, M.; Islam, R.; Lipton, Ronald; Tricoli, A.; Chen, W.
• Is Part Of: Journal of physics. Volume 2374 Issue 1(2022)
• Publication Date: 2022-11-01
• Subjects: Physics -- Congresses; 530.5
• DOI: 10.1088/1742-6596/2374/1/012166
• Languages: English
• ISSNs: 1742-6588

Abstract

Abstract : We report on the design, simulation and test of Low Gain Avalanche Diodes (LGADs) which utilize a buried gain layer. The buried layer is formed by patterned implantation of a 50-micron thick float zone substrate wafer-bonded to a low resistivity carrier. This is then followed by epitaxial deposition of a ≈ 3 micron-thick high resistivity amplification region. The topside is then processed with junction edge termination and guard ring structures and incorporates an AC-coupled cathode implant. This design allows for independent adjustment of gain layer depth and density, increasing design flexibility. A higher gain layer dopant density can also be achieved by controlling the process thermal budget, improving radiation hardness. A first set of demonstration devices has been fabricated, including a variety of test structures. We report on TCAD design and simulation, fabrication process flow, and preliminary measurements of prototype devices.