Abstract: A field effect transistor includes a substrate having a transistor forming region thereon; an insulating layer on the substrate; a first graphene layer on the insulating layer within the transistor forming region; an etch stop layer on the first graphene layer within the transistor forming region; a first inter-layer dielectric layer on the etch stop layer; a gate trench recessed into the first inter-layer dielectric layer and the etch stop layer within the transistor forming region; a second graphene layer on interior surface of the gate trench; a gate dielectric layer on the second graphene layer and on the first inter-layer dielectric layer; and a gate electrode on the gate dielectric layer within the gate trench.

Abstract: A coffee grinding machine includes a base, a motor and a grinding device. The motor is mounted in the base. The base has a top face provided with a platform for mounting the grinding device. The grinding device includes an outer cutter and an inner cutter. A bearing is mounted on the outer cutter to drive the outer cutter so that the outer cutter is rotated above the inner cutter to grind the falling coffee beans into coffee powders. Thus, the coffee powders fall down vertically and will not remain in the grinding device.

Abstract: A coffee grinding machine includes a base, a motor and a grinding device. The motor is mounted in the base. The base has a top face provided with a platform for mounting the grinding device. The grinding device includes an outer cutter and an inner cutter. A bearing is mounted on the outer cutter to drive the outer cutter so that the outer cutter is rotated above the inner cutter to grind the falling coffee beans into coffee powders. Thus, the coffee powders fall down vertically and will not remain in the grinding device.