Abstract: A method for preparing a gate oxide layer is described. First, a trench surrounding an active area is formed in a substrate, and a dielectric block is then formed in the trench such that an upper surface of the dielectric block is not aligned with that of the substrate. Subsequently, an ion implantation process is performed to implant nitrogen-containing dopants into the substrate in the active area, and a thermal oxidation process is then performed to form a gate oxide layer on the surface of the substrate in the active area. Particularly, the concentration of the nitrogen-containing dopants at the center of the active area is higher than that at the edge of the active area. The nitrogen-containing dopants inhibit the reaction rate of the thermal oxidation process, so as to prevent the gate oxide layer from thinning at the edge near the trench.

Abstract: A universal entertainment system includes an entertainment unit, a universal mounting stand, and a folding joint. The entertainment unit includes an entertainment housing having a multimedia compartment, a display screen provided on a screen side, and a multi-functional multimedia circuitry disposed in the multimedia compartment for reading digital data of a multimedia. The universal mounting stand is adapted for supporting at a fixture surface. The folding joint pivotally connects the entertainment unit with the universal mounting stand in a rotatably movable manner, wherein the entertainment unit is adapted to pivotally fold with respect to the universal mounting stand to selectively adjust a tilt angle of the display screen with respect to the fixture surface and is adapted to rotatably fold with respect to the universal mounting stand to selectively adjust a revolving angle with respect to the universal mounting stand.