摘要:
Composite roofing boards and methods for installing a composite roofing board are presented herein. In one embodiment, the roofing board comprises at least nine layers: two outer polymeric layers; two adhesive layers disposed between the two outer polymeric layers; two inner polymeric layers disposed between the two adhesive layers; and a substrate layer disposed between the two inner polymeric layers. A polymeric adhesive, such as an acrylate-polymer adhesive, is preformed on an outer surface of the first and/or second outer polymeric layer. A removable release liner, such as a siliconized polyester film, covers the polymeric adhesive.
摘要:
An overmolded pressure sensor package is provided. The pressure sensor die (Pcell) is capped so that the Pcell has enhanced rigidity to withstand stress effects produced by the molding encapsulant. The Pcell cap includes a hole located away from the Pcell diaphragm, so that external gas pressure can be experienced by the Pcell, while at the same time directing moisture away from the diaphragm. Gel does not need to be used, and instead a soft film can be deposited on the Pcell to protect the Pcell diaphragm from excess moisture, if needed. The Pcell cap can take the form of, for example, a dummy silicon wafer or a functional ASIC.
摘要:
Methods and apparatus are provided for decreasing the size of Quad Flat No-Lead (QFN) packages (300, 400) down to chip-scale packages. Such QFN packages include a first semiconductor chip (310, 410), a plurality of recessed leads (306, 406, 408, 411) having mold lock features, and a mold material 340, 440 substantially encasing all sides of the semiconductor chip. An active surface (314, 414) of the semiconductor chip is oriented toward a mounting side (307, 407) of the QFN package, and a plurality of wire bonds 330, 430 disposed between the active surface and the mounting side couple the active side to the leads. The QFN packages may also include a second semiconductor chip (452) coupled to a plurality of leads (408) and to the first semiconductor chip via wire bonds (431, 432) in a manner similar to the first semiconductor chip.
摘要:
A MEMS device (100) is provided that includes a handle layer (108) having a sidewall (138), a cap (132) overlying said handle layer (108), said cap (132) having a sidewall (138), and a conductive material (136) disposed on at least a portion of said sidewall of said cap (138) and said sidewall of said handle layer (138) to thereby electrically couple said handle layer (108) to said cap (132). A wafer-level method for manufacturing the MEMS device from a substrate (300) comprising a handle layer (108) and a cap (132) overlying the handle layer (108) is also provided. The method includes making a first cut through the cap (132) and at least a portion of the substrate (300) to form a first sidewall (138), and depositing a conductive material (136) onto the first sidewall (138) to electrically couple the cap (132) to the substrate (300).
摘要:
Methods are provided for manufacturing a sensor. The method comprises depositing a sacrificial material at a first predetermined thickness onto a wafer having at least one sense element mounted thereon, the sacrificial material deposited at least partially onto the at least one sense element, forming an encapsulating layer at a second predetermined thickness less than the first predetermined thickness over the wafer and around the deposited sacrificial material, and removing the sacrificial material. Apparatus for a sensor manufactured by the aforementioned method are also provided.
摘要:
A method and structure that protects interior electrical components of a pressure sensor (4) from corrosive particles using a sacrificial gel dome (30) to form a vent (34) in a protective gel (32) that covers electrical components that can be corroded such as wires (16), bond pads (18), and electrical leads (14). Sacrificial gel dome (30) is dispensed over a diaphragm (28) of pressure sensor (4) to form vent (34) enabling diaphragm (28) to sense pressure variations without the influence of protective gel (32). Sacrificial gel dome (30) is removed through a water rinsing process (42) to expose vent (34).
摘要:
Fabrication methods are provided for a sensor device packages. An exemplary fabrication method involves bonding a sensor structure and another structure using a sealing structure. The sealing structure surrounds a diaphragm region of the sensor structure and provides an airtight seal between the sensor structure and the other structure to establish a fixed reference pressure on one side of the diaphragm region.
摘要:
A dual port pressure sensor has a lead frame having a flag having a first opening and a second opening. The lead frame has a flag having a first opening and a second opening. An encapsulant holds the lead frame. The encapsulant is over a top of the flag and a bottom of the flag is uncovered by the encapsulant. A first opening in the encapsulant is aligned with and larger than the first opening in the flag, and a second opening in the encapsulant is aligned with the second opening in the flag. A pressure sensor transducer is attached to the bottom of the flag and covers the first opening in the flag and provides an electrically detectable correlation to a pressure differential based on a first pressure received on its top side and a second pressure received on its bottom side. An integrated circuit is attached to the bottom of the flag and is electrically coupled to the pressure sensor. A lid forming an enclosure with the bottom of the flag. The pressure sensor transducer receives the first pressure through the first opening in the encapsulant and the first opening in the flag and the second pressure through the second opening in the encapsulant, the second opening in the flag, and the enclosure.
摘要:
A method and apparatus are described for fabricating an exposed backside pressure sensor (30) which protects interior electrical components (37) formed on a topside surface of a pressure sensor transducer die (31) from corrosive particles using a protective gel layer (38) and molding compound (39), but which vents a piezoresistive transducer sensor diaphragm (33) formed on a backside of the pressure sensor transducer die (31) through a vent hole (42) formed in an exposed die flag (36), enabling the sensor diaphragm (33) to directly sense pressure variations without the influence of a protective gel.
摘要:
Methods are provided for forming Quad Flat No-Lead (QFN) packages. An embodiment includes disposing an active side of a semiconductor chip on a plurality of leads, coupling a plurality of wire bonds to the active side of the semiconductor chip, coupling the plurality of wire bonds to the plurality of leads in a space between the active side and the plurality of leads, and encasing the semiconductor chip, at least a portion of each of the plurality of leads, and the plurality of wire bonds in a mold material to define a mounting side of the QFN package. The mounting side has a perimeter, the plurality of leads are oriented on and exposed on the mounting side within the perimeter, and the plurality of wire bonds are oriented between the active side and the mounting side within the mold material.