A transistor includes: a substrate (100) with a channel region; a source region (101) and a drain region (102) on opposite ends of the channel region of the substrate (100); a high-k gate dielectric layer (103) on the top surface of the substrate (100) above the channel region between the source region (101) and the drain region (102); an interface layer under the high-k gate dielectric layer (103), a first portion (107) thereof close to the source region (101), a second portion (106) thereof close to the drain region (102), the equivalent oxide thickness of the first portion (107) is greater than that of the second portion (106). An asymmetric interface layer caused by a dual material asymmetric gate can help suppress the short channel effect at the drain side and avoid decreasing the mobility of carriers at the source side. In addition, the asymmetric gate can have different work functions.