Modification of etched junction termination extension for the high voltage 4H-SiC power devices

• High voltage 4H-SiC bipolar junction transistors (BJTs) with modified etched junction termination extension (JTE) were fabricated and optimized in terms of the length (LJTE) and remaining dose (DJTE) of JTEs. It is found that for a given total termination length (Σ LJTEi), a decremental JTE length from the innermost edge to the outermost mesa edge of the device will result in better modification of the electric field. A breakdown voltage (BV) of 4.95 kV is measured for the modified device which shows ~20% improvement of the termination efficiency for no extra cost or extra process step. Equal-size BJTs by interdigitated-emitter with different number of fingers and cell pitches were fabricated. The maximum current gain of 40 is achieved for a single finger device with the emitter width of 40 μm at IC = 0.25 A (JC = 310 A/cm2) which corresponds to RON = 33 mΩ.cm2. It is presented that the current gain decreases by having more fingers while the maximum current gain is achieved at higher current density.

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

4H-SiC

BJT

Etched junction termination extension

High voltage

Publication and Content Type

ref (subject category)

kon (subject category)