The invention discloses
a diamond MOSFET device compatible with a
CMOS ohmic contact process and a preparation method of the
diamond MOSFET device. The preparation method comprises the steps that S1,
a diamond substrate is selected, and an intrinsic
diamond layer is grown on the
diamond substrate in a homoepitaxial mode; s2, preparing a
mask, and forming a
boron-doped diamond layer in a source region and a drain region on the intrinsic diamond layer through
boron ion implantation; s3, depositing a layer of Si film and a layer of Ti film on the surface of the sample; s4, performing two-step annealing on the sample to obtain
ohmic contact formed by the
boron-doped diamond layer, the boron-doped
silicon layer and the
titanium silicide layer; s5, removing the
mask and the thin film above the
mask; s6, preparing a terminal diamond
surface layer; s7, preparing a
passivation layer and windowing to form a source window and a drain window; and S8, preparing a gate
electrode. According to the method, high-quality
ohmic contact can be formed on the diamond through the gold-free process, the gold
ion pollution risk is thoroughly avoided, and
CMOS process compatibility is achieved.