Abstract: A semiconductor device comprising: a lower insulating layer; a field insulating layer on the lower insulating layer; an upper insulating layer on the field insulating layer; a first through via in the upper insulating layer; a second through via in the field insulating layer; and a third through via in the lower insulating layer, wherein the second through via is connected to the first and third through vias, and wherein a width of a top surface of the second through via is greater than a width of a bottom surface of the first through via, a width of a bottom surface of the second through via is greater than a width of a top surface of the third through via, and a width of a middle portion of the second through via is greater than the widths of the top surface and the bottom surface of the second through via.

Abstract: A wrist supporting chassis is mounted on independent swiveling rollers for carrying the wrist of a user of a pointing device such as a computer mouse on a desktop or other surface. The swiveling rollers are carried on swivel arms in recesses on an underside of the chassis, arranged to rotate freely on a vertical axis, perpendicular to the desktop or surface. The swivel arms define a radius from the swivel axis to a roller carried on an axle parallel to the desktop and perpendicular to both the radius and the swivel axis. The swivel arm is mounted to the chassis by a hub that fits into a collar with an intervening bushing or ball bearing. In exemplary embodiments, the swivel arm can be a disc with a central hub, the roller axle being heat-pressed into the disc to occupy a radial slot at the outer edge of the disc. Alternatively, a spring biased arrangement for the roller axle can be provided on facing channels the define a range of roller displacement.