Abstract:
A released beam structure fabricated in trench and manufacturing method thereof are provided herein. One embodiment of a released beam structure according to the present invention comprises a semiconductor substrate, a trench, a first conducting layer, and a beam. The trench extends into the semiconductor substrate and has walls. The first conducting layer is positioned over the walls of the trench at selected locations. The beam is positioned with the trench and is connected at a first portion thereof to the semiconductor substrate and movable at a second portion thereof. The second portion of the beam is spaced from the walls of the trench by a selected distance. Therefore, the second portion of the beam is free to move in a plane that is perpendicular or parallel to the surface of the substrate, and could be deflected to electrically contact with the walls of the trench in response to a predetermined acceleration force or a predetermined temperature variation applied on the beam structure. Other beam structures such as a beam held at both ends, or a beam held in the middle are also possible. Several beam structures at different angles can be fabricated simultaneously and mechanical etching stops are automatically formed to prevent unwanted overstress conditions when manufacturing several beam structures at the same time. Beam structures can also be manufactured in three orthogonal directions, providing information on acceleration in any direction.
Abstract:
A low-voltage high-current discrete insulated-gate field-effect transistor which is made by a very economical process with two silicon etches. A buried poly gate gates conduction along a trench sidewall. The channel is provided by the residuum of an epi layer, and the source diffusion is provided by an unmasked implant which is screened only by various grown oxides.
Abstract:
A released beam structure fabricated in trench and manufacturing method thereof are provided herein. One embodiment of a released beam structure according to the present invention comprises a semiconductor substrate, a trench, a first conducting layer, and a beam. The trench extends into the semiconductor substrate and has walls. The first conducting layer is positioned over the walls of the trench at selected locations. The beam is positioned with the trench and is connected at a first portion thereof to the semiconductor substrate and movable at a second portion thereof. The second portion of the beam is spaced from the walls of the trench by a selected distance. Therefore, the second portion of the beam is free to move in a plane that is perpendicular or parallel to the surface of the substrate, and could be deflected to electrically contact with the walls of the trench in response to a predetermined acceleration force or a predetermined temperature variation applied on the beam structure. Other beam structures such as a beam held at both ends, or a beam held in the middle are also possible. Several beam structures at different angles can be fabricated simultaneously and mechanical etching stops are automatically formed to prevent unwanted overstress conditions when manufacturing several beam structures at the same time. Beam structures can also be manufactured in three orthogonal directions, providing information on acceleration in any direction.
Abstract:
There is provided protection for a first pad of an integrated circuit, the integrated circuit having a second pad to receive a first supply voltage. A first region of a first conductivity type is coupled to the first pad; a second region of a second conductivity type is coupled to the second pad; a substrate of the second conductivity type contacts the first and second regions; and there is an epitaxial layer of the first conductivity type. An epitaxial region contacts the first and second regions. A first diode can be formed outside the substrate between the first and second pads through at least two of the first region, the second region, and the epitaxial region. The protection structure may include first and second portions, each portion having a different voltage threshold. The first diode can be formed through the second portion, but not the first portion.