Retrograde p-well for 10-kv class sic igbts

Tiwari, Amit K.; Antoniou, Marina; Lophitis, Neophytos; Perkin, Samuel; Trajkovic, Tatjana; Udrea, Florin

Abstract

In this paper, we propose the use of a retrograde doping profile for the p-well for ultrahigh voltage (>10 kV) SiC IGBTs. We show that the retrograde p-well effectively addresses the punchthrough issue, whereas offering a robust control over the gate threshold voltage. Both the punchthrough elimination and the gate threshold voltage control are crucial to high-voltage vertical IGBT architectures and are determined by the limits on the doping concentration and the depth that a conventional p-well implant can have. Without any punchthrough, a 10-kV SiC IGBT consisting of retrograde p-well yields gate threshold voltages in the range of 6-7 V with a gate oxide thickness of 100 nm. Gate oxide thickness is typically restricted to 50-60 nm in SiC IGBTs if a conventional p-well with 1×10 17 cm -3 is utilized. We further show that the optimized retrograde p-well offers the most optimum switching performance. We propose that such an effective retrograde p-well, which requires low-energy shallow implants and thus key to minimize processing challenges and device development cost, is highly promising for the ultrahigh-voltage (>10 kV) SiC IGBT technology.

• Journal Article Type: Article
• Acceptance Date: May 16, 2019
• Online Publication Date: Jun 3, 2019
• Publication Date: Jul 1, 2019
• Deposit Date: Apr 24, 2020
• Publicly Available Date: Apr 24, 2020
• Journal: IEEE Transactions on Electron Devices
• Print ISSN: 0018-9383
• Electronic ISSN: 1557-9646
• Publisher: Institute of Electrical and Electronics Engineers
• Peer Reviewed: Peer Reviewed
• Volume: 66
• Issue: 7
• Pages: 3066-3072
• DOI: https://doi.org/10.1109/TED.2019.2918008
• Public URL: https://nottingham-repository.worktribe.com/output/3706485
• Publisher URL: https://ieeexplore.ieee.org/document/8728169
• Additional Information: © 2019 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.