ESD Safe Conductive Lapping Plate
Original Publication Date: 2002-Sep-09
Included in the Prior Art Database: 2003-Jun-20
This invention describes a process to produce a lapping plate with virtually no adhesive between the diamond or other abrasive particles. This leaves the bulk of the substrate or plate exposed. Using a conductive adhesive to bond the particles to the plate and a conductive plate would produce a lapping plate, which creates no ESD problems. It is useable for particle sizes in the micron to sub-micron range. This process may also be used with substrates which are not conductive to produce an alternative bonding technique for abrasive particles. It may also be used with non-conductive substrates by coating them with a conductive surface prior to deposition. The basic idea is to distribute diamond particles or other abrasives on a substrate in a uniform manner and then encapsulate the particles with a conductive adhesive or media followed by an optional process which exposes the diamond embedded in the surface. The expose process can be a simple mechanical abrasion of the surface which will expose the abrasive particles but leave the coating between the particles or it can be a RIE or other plasma process which removes the coating from the top of the particles as well as the substrate but leaves the side wall to anchor the particles to the surface. The lapping plate is composed of a disk or other low cost substrate, e.g. glass disk used in DASD mfg, silicon wafer, quarts plate, etc., which is coated with diamond particles of the size appropriate for the particular use of the lapping plate. These particles adhere to the surface of the disk (or both surfaces of the disk) via electrostatic attraction or other mechanism. The plates are then placed in a CVD deposition reactor or other similar deposition system where a conductive material is deposited on the plates. This material conformally coats the diamond particles bonding them to the plate or substrate. Using a conductive deposition such as Poly Silicon, metal or other material results in a permanent bond of the particles to the substrate.