Abstract: A semiconductor device is provided. The semiconductor device includes a substrate, a stacked gate structure, and a wall structure. The stacked gate structure is on the substrate and extending along a first direction. The wall structure is on the substrate and laterally aside the stacked gate structure. The wall structure extends along the first direction and a second direction perpendicular to the first direction. The stacked gate structure is overlapped with the wall structure in the first direction and the second direction.

Abstract: A drawing board assembly includes a board having two tracks and two slide bases are movably received in the tracks. A ruler is connected between the two slide bases and a frame is connected to the ruler. The frame has a groove in which a slide member is movably received. A protractor is connected to the slide member and a guide ruler is pivotally connected to the protractor. A bolt extends through the guide ruler and the protractor. A positioning knob is connected to the bolt so that when the bolt is loosened, the guide ruler is pivoted.

Abstract: A drawing board assembly includes a rectangular board including two opposite end portions each having a side wall transversely defining an elongate guiding track therein and a top wall. Two inverted L-shaped sliding bases are each slidably supported on a corresponding one of the two end portions of the board and each include a first plate abutting on the top wall and a second plate abutting on the side wall. Two slides are each fixedly mounted on the second plate of a corresponding one of the two sliding bases and are each slidably received in the guiding track A ruler is slidably mounted on the board, and an elongate frame is fixedly mounted on the ruler and includes two end portions each connected with the first plate of a corresponding one of the two sliding bases.

Abstract: A drafting device includes a pair of magnetic boards securely mounted to upper and lower surfaces of a base frame respectively, a ruler movably engaged on the magnetic board, a pair of cavities defined in each of the four corners of the lower surface of the base frame, and a protrusion being formed between the pair of cavities. A guiding member is securely mounted to each of the four corners of the base frame and includes a locking block having a first wall member and a second wall member mounted on the upper and lower surfaces of the base frame respectively, a slot being defined in the second wall member through which the protrusion is received, a recess defined in an underside of the locking block between the first and second wall members and having a width equal to the distance between a bottom face of the cavity and the upper surface of the base frame. A guiding line loops around each of the guiding members and passes through two ends of the ruler.

Abstract: A protractor including a base having a curved surface formed in an upper portion, a disc including a circular outer peripheral surface for slidable engagement with the curved surface of the base, the disc including an opening, a pair of flanges formed in parallel in the opening, and a slide including two end portions slidably engaged with the flanges of the disc so that the slide can be guided to slide along the flanges, whereby various geometric figures can be drawn by the protractor when the disc rotates relative to the base and when the slide slides along the flanges.