Abstract: A cooling structure for a heat source, where the cooling structure includes a beam having a first end and a second end and a length disposed therebetween. The beam is formed at least in part of a first material having a first thermal coefficient of expansion and a second material having a second thermal coefficient of expansion, where the first thermal coefficient of expansion is different from the second thermal coefficient of expansion. The first end of the beam is thermally connected to the heat source, such that heat generated by the heat source is conducted along the length of the beam to the second end of the beam. The heat conducted through the beam causes the beam to deflect as the first and second materials expand differently due to the difference in the first and second thermal coefficients of expansion.

Abstract: A novel fabrication process uses a combination of negative and positive photoresists with positive tone photomasks, resulting in masking layers suitable for bulk micromachining high-aspect ratio microelectromechanical systems (MEMS) devices. This technique allows the use of positive photomasks with negative resists, opening the door to an ability to create complementary mechanical structures without the fabrication delays and costs associated with having to obtain a negative photomask. In addition, whereas an SU-8 mask would normally be left in place after processing, a technique utilizing a positive photoresist as a release layer has been developed so that the SU-8 masking material can be removed post-etching.

Abstract: A MEMS switch fabrication process and apparatus inclusive of a bulbous rounded surface movable contact assembly that is integral with the switch movable element and achieving of long contact wear life with low contact electrical resistance. The disclosed process is compatible with semiconductor integrated circuit fabrication materials and procedures and includes an unusual photoresist reflow step in which the bulbous contact shape is quickly defined in three dimensions from more easily achieved integrated circuit mask and etching-defined precursor shapes. A plurality of differing photoresist materials are used in the process. A large part of the contact and contact spring formation used in the invention is accomplished with low temperature processing including electroplating. Alternate processing steps achieving an alloy metal contact structure are included. Use of a subroutine of processing steps to achieve differing but related portions of the electrical contact structure is also included.

Abstract: A MEMS switch fabrication process and apparatus inclusive of a bulbous rounded surface movable contact assembly that is integral with the switch movable element and achieving of long contact wear life with low contact electrical resistance. The disclosed process is compatible with semiconductor integrated circuit fabrication materials and procedures and includes an unusual photoresist reflow step in which the bulbous contact shape is quickly defined in three dimensions from more easily achieved integrated circuit mask and etching-defined precursor shapes. A plurality of differing photoresist materials are used in the process. A large part of the contact and contact spring formation used in the invention is accomplished with low temperature processing including electroplating. Alternate processing steps achieving an alloy metal contact structure are included. Use of a subroutine of processing steps to achieve differing but related portions of the electrical contact structure is also included.

Abstract: A method for selecting metal alloys as the electric contact materials for microelectromechanical systems (MEMS) metal contact switches. This method includes a review of alloy experience, consideration of equilibrium binary alloy phase diagrams, obtaining thin film material properties and, based on a suitable model, predicting contact electrical resistance performance. After determination of a candidate alloy material, MEMS switches are conceptualized, fabricated and tested to validate the alloy selection methodology. Minimum average contact resistance values of 1.17 and 1.87 ohms are achieved for micro-switches with gold (Au) and gold-platinum (Au-(6.3 at %)Pt) alloy contacts. In addition, ‘hot-switched’ life cycle test results of 1.02×108 and 2.70×108 cycles may be realized for micro-switches with Au and Au-(6.3 at %)Pt contacts. These results indicate increased wear with a small increase in contact resistance for MEMS switches with metal alloy electric contacts.