Chemical Vapor Deposition Carbon Film as a Capping Layer in 4H-SiC Based MOSFETs

Abstract

Radio-frequency plasma enhanced CVD (RF-PECVD) carbon films were grown directly on 4-inch 4H-SiC substrates as a capping layer for MOSFET device applications. An approximately 50-nm-thick CVD carbon capping layer was found to reduce the surface roughness, as determined by atomic force microscopy (AFM). The secondary ion mass spectroscopy (SIMS) depth profile results revealed that carbon capping layer can suppress the dopant out-diffusion on the implanted surface after annealing even at high temperature (1700 °C) for 30 min. The calculated subthreshold swing (S) values of devices with CVD carbon capping layer and photo-resist process (base) measured at room temperature were 460 ± 50 (mV/dec) and 770 ± 70 (mV/dec), respectively. The lower value of 'S' for the device with carbon capping layer was related to the very low density of interface traps at the SiC-SiO2 interface. These results show the potential of CVD carbon as a capping layer for SiC MOSFET device applications.

Thermal stability study of Ni–Si silicide films on Ni/4H-SiC contact by in-situ temperature-dependent sheet resistance measurement

“…To fabricate a high power device, a typical MOSFET fabrication process was used. 16) The doping concentration and thickness of the epitaxial layer (N-drift region) were 5 × 10 15 cm −3 and 11.5 μm, respectively, for a 1200 V MOSFET on a 4°4H-SiC (0001) substrate. Typical doses and energies of each implantation condition and the key process conditions for the silicide and metal are described in our previous report (see Ref.…”

“…Typical doses and energies of each implantation condition and the key process conditions for the silicide and metal are described in our previous report (see Ref. 16 for more details). After the formation of the SiO 2 mask, n + regions were formed by N ion implantation at a dose of ∼1 × 10 15 cm −2 and energy of 220 keV, while p + (dose of ∼1 × 10 15 cm −2 and energy of 80 keV) and p-well regions were formed by Al ion implantation.…”

Recent Progress in Magnetron Sputtering Technology Used on Fabrics

“…Nano-films are widely used in electronics, textiles, biomedicine, ceramics and other fields [ 1 , 2 , 3 , 4 , 5 , 6 ]. Fabrics coated with Nano film are usually prepared through chemical vapor deposition [ 7 ], chemical deposition [ 8 , 9 ], sol-gel [ 10 ] method and magnetron sputtering [ 11 ]. Among them, the magnetron sputtering method has the advantages of controllable film thickness, high purity, high speed and low temperature, favorable adhesion, easy operation, and environmental friendliness, etc.…”