High resolution powder blast micromachining

Powder blasting, or Abrasive Jet Machining (AJM), is a technique in which a particle jet is directed towards a target for mechanical material removal. It is a fast, cheap and accurate directional etch technique for brittle materials like glass, silicon and ceramics. By introducing electroplated copper as a new mask material, the feature size of this process was decreased. It was found that blasting with 9 μm particles (compared with 30 μm particles) result in a higher slope of the channel sidewall. The aspect ratio of powder blasted channels was increased by using the high resistance of the copper mask in combination with the use of 9 μm particles. Furthermore, our measurements show how the blast lag (small channels etch slower compared to wider channels) is decreased by using smaller particles