Abstract: A method for forming a high electron mobility transistor is disclosed. A mesa structure having a channel layer and a barrier layer is formed on a substrate. The mesa structure has two first edges extending along a first direction and two second edges extending along a second direction. A passivation layer is formed on the substrate and the mesa structure. A first opening and a plurality of second openings connected to a bottom surface of the first opening are formed and through the passivation layer, the barrier layer and a portion of the channel layer. In a top view, the first opening exposes the two first edges of the mesa structure without exposing the two second edges of the mesa structure. A metal layer is formed in the first opening and the second openings thereby forming a contact structure.

Abstract: A method for fabricating a high electron mobility transistor (HEMT) includes the steps of forming a buffer layer on a substrate, forming a barrier layer on the buffer layer, forming a p-type semiconductor layer on the barrier layer, forming a gate electrode layer on the p-type semiconductor layer, and patterning the gate electrode layer to form a gate electrode. Preferably, the gate electrode includes an inclined sidewall.

Abstract: A flexible flat cable contains mainly multiple lines of conductive cable which is elongated to gain better ductility and pressed to change it into a flat cable, encased both on the top and bottom surface with a layer of insulation. The exposed ends of the cable become a section of conductor, on which it is coated with a metal and finally stiffened with reinforcement to become a reliable flexible flat cable. The utmost surface of the conductive ends is further gilt to enhance its conductivity so as to intensify the data transmission efficient when used in LVDS. The purpose of the gilt coating is to harden the cable surface and to restrain the generation of tin tassel from tin coating which would render short circuit in the flat cable.

Abstract: The invention relates to a structure of a metal spring plate. The opposite edges of a peripheral rim of the metal spring plate are cut straight. The peripheral rim is smoothed out to avoid metal danglers so fatigue fracture due to residual stress won't happen on the metal spring plate after long term wear and tear. Furthermore, a center atop the metal spring plate can be an protrusion or an indentation to enhance feel of response for a cell phone user and to ensure accurate signal input.