Abstract: A semiconductor device having a highly reliable groove isolation structure with a desired radius of curvature formed at the groove upper edge and without formation of any step, there is produced by reducing the stress generation around the groove upper edge of an element isolation groove on a semiconductor substrate, thereby optimizing the shape of an element isolation groove and making the device finer and improving the device electric characteristics.

Abstract: An end node for which sending and receiving are controlled by a hub is directly connected and used. When another end node is directly connected to the PMD control unit 2, the input control signal processor 11 of the signal processor 1 receives a receiving state signal indicating the state of a tone signal which is outputted from the PMD control unit 2 and received from another end node, converts it to a receiving state signal indicating the state of a tone signal from the hub which has the same meaning as it, and transfers it to the MAC/PMI control unit 4.

Abstract: A method for producing a display window for a communication device covering a display element. The method includes the steps of providing a moulding tool with a matt surface structure, injecting fluid plastics, and cooling of the injected plastics and releasing the display window.