Micromachining of diamond film for MEMS applications

Abstract

We realized two diamond microdevices: a movable diamond microgripper and a diamond probe for an atomic force microscope (AFM), consisting of a V-shaped diamond cantilever and a pyramidal diamond tip, using a microfabrication technique employing semiconductive chemical-vapor-deposited diamond thin film. The microgripper was fabricated by patterning diamond thin film onto a sacrificial SiO 2 layer by selective deposition and releasing the movable parts by sacrificial layer etching. The diamond AFM probe was fabricated by combining selective deposition for patterning a diamond cantilever with a mold technique on an Si substrate for producing a pyramidal diamond tip. The cantilever was then released by removing the substrate. We report the initial results obtained in AFM measurements taken using the fabricated diamond probe. These results indicate that this diamond probe is capable of measuring AFM images. In addition, we have developed the anodic bonding of diamond thin film to glass using Al or Ti film as an intermediate layer for assembly. This bonding technique will allow diamond microstructures to be used in many novel applications for microelectromechanical systems. [397]Index Terms-Diamond AFM probe, diamond film, diamond microstructures, MEMS, micromachining.

Recent Developments in Polymer MEMS

“…The MEMS field provided incentives for the conceptualization and sustained development of such processes as deep reactive ion etching, photodefinable SU-8 epoxy, [18] and self-assembly. [19] Over the years, the MEMS field has steadily expanded its material base to include compound semiconductors, [20,21] diamond, [22][23][24] and ceramics. [25,26] Polymer is a large class of material that includes three major categories: fibers, plastics, and elastomers.…”

Developing a New Material for MEMS: Amorphous Diamond

“…Recently, researchers have made considerable progress in the fabrication of MEMS structures fabricated from polycrystalline and nanocrystalline diamond, both in the area of surface micromachining and in mold-based processes [3][4][5][6][7][8][9][10][11][12][13]. A variety of diamond microstructures have been demonstrated, including substrates with integrated channels for active-cooling [3], micromachined fresnel optics [3], optical fiber alignment structures [4], free-standing capillary tubes [4], acceleration sensors [5], thermally-actuated liquid ejectors [5], electrical microswitches [6], micro-tweezers [7], diamond cantilevers with tips for scanning probe microscopy (SPM) applications [7], a diamond motor structure [8], diamond gears [9,10], and nanoindentation tips [11]. Most of these structures are fabricated from chemical vapor deposited (CVD) polycrystalline diamond.…”

<title>Patterning of diamond microstructures on Si substrate by bulk and surface micromachining</title>

“…Diamond thin films have been receiving much attention for potential high-performance electronic devices and microelectromechanical (MEMS) applications (especially in hostile environments, such as high ambient temperatures, reactive environment or extensive wear and friction conditions), mainly due to their excellent thermal, mechanical, electrical and chemical properties as well as wide band gap [1,2,3]. Selective deposition and precise patterning of diamond microstructures is a key technology in the application of diamond to micro-electronic devices and MEMS.…”