Investigation of the breakdown voltage in high voltage 4H-SiC BJT with respect to oxide and interface charges

• Ion implantation in silicon carbide (SiC) induces defects during the process. Implantation free processing can eliminate these problems. The junction termination extension (JTE) can also be formed without ion implantation in SiC bipolar junction transistor (BJT) using a well-controlled etching into the epitaxial base layer. The fixed charges at the SiC/SiO2 interface modify the effective dose of the JTEs, leakage current, and breakdown voltage. In this paper the influence of fixed charges (positive and negative) and also interface trap density at the SiC/SiO2 interface on the breakdown voltage in 4.5 kV 4H-SiC non-ion implanted BJT have been simulated. SiO2 as a surface passivation layer including interface traps and fixed charges has been considered in the analysis. Simulation result shows that the fixed charges influence the breakdown voltage significantly more than the interface traps. It also shows that the positive fixed charges reduce the breakdown voltage more than the negative fixed charges. The combination of interface traps and fixed charges must be considered when optimizing the breakdown voltage.

Subject headings

TEKNIK OCH TEKNOLOGIER  -- Elektroteknik och elektronik -- Annan elektroteknik och elektronik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Electrical Engineering, Electronic Engineering, Information Engineering -- Other Electrical Engineering, Electronic Engineering, Information Engineering (hsv//eng)

Keyword

Bipolar junction transistor (BJT)

Fixed charges

Implantation free

Interface traps

Junction termination extension (JTE)

Oxide

Silicon carbide (SiC)

Electric breakdown

Heterojunction bipolar transistors

Ion implantation

Ions

Oxides

Silicon

Silicon carbide

Silicon oxides

Transistors

Interface trap density

Junction termination extensions

Negative fixed charge

SiC bipolar junction transistors

Silicon carbides (SiC)

Surface passivation

Bipolar transistors

Informations- och kommunikationsteknik

Information and Communication Technology

Publication and Content Type

ref (subject category)

art (subject category)