Study of bulk and elementary screw dislocations assisted reverse breakdown in low-voltage (<250 V) 4H-SiC p{sup +}n junction diodes. Part 1: DC properties

Journal Article · Mon Mar 01 04:00:00 EST 1999 · IEEE Transactions on Electron Devices

DOI:https://doi.org/10.1109/16.748865· OSTI ID:334079

Neudeck, P G ^[1]; Huang, W; Dudley, M ^[2]

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1. NASA Lewis Research Center, Cleveland, OH (United States)
2. State Univ. of New York, Stony Brook, NY (United States). Dept. of Materials Science and Engineering

Given the high-density ({approximately}10{sup 4} cm{sup {minus}2}) of elementary screw dislocations (Burgers vector = 1c with no hollow core) in commercial SiC wafers and epilayers, all large current (>1 A) SiC power devices will likely contain elementary screw dislocations for the foreseeable future. It is therefore important to ascertain the electrical impact of these defects, particularly in high-field vertical power device topologies where SiC is expected to enable large performance improvements in solid-state high-power systems. This paper compares the dc-measured reverse-breakdown characteristics of low-voltage (<250 V) small-area (<5 {times} 10{sup {minus}4} cm{sup 2}) 4H-SiC p{sup +}n diodes with and without elementary screw dislocations. Diodes containing elementary screw dislocations exhibited higher pre-breakdown reverse leakage currents, softer reverse breakdown current-voltage (I-V) knees, and highly localized microplasmic breakdown current filaments compared to screw dislocation-free devices. The observed localized 4H-SiC breakdown parallels microplasmic breakdown observed in silicon and other semiconductors, in which space-charge effects limit current conduction through the local microplasma as reverse bias is increased.

• Research Organization: Brookhaven National Laboratory (BNL), Upton, NY
• Sponsoring Organization: National Aeronautics and Space Administration, Washington, DC (United States); Defense Advanced Research Projects Agency, Arlington, VA (United States); Department of the Army, Washington, DC (United States); USDOE, Washington, DC (United States)
• DOE Contract Number: AC02-76CH00016
• OSTI ID: 334079
• Journal Information: IEEE Transactions on Electron Devices, Journal Name: IEEE Transactions on Electron Devices Journal Issue: 3 Vol. 46; ISSN IETDAI; ISSN 0018-9383
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
BREAKDOWN
JUNCTION DIODES
P-N JUNCTIONS
SCREW DISLOCATIONS
SILICON CARBIDES