Microfluidic And Optical Molds
Diffractive Optics, Microfluidics and devices for Micro-Electro-Mechanical Systems (MEMS) utilize finely patterned surfaces, with feature sizes from nanometers to several millimeters. These intricate structures can be diamond machined, created photolithographically, or produced by laser and/or chemical etching in such delicate materials as silicon wafers, quartz, glass, and select polymers. In many cases, pattern generation is an expensive and time consuming process.
As an enabling technology, electroforming provides a way to accurately and cost-effectively transfer such intricate patterns from fragile or otherwise unstable substrates into durable NiColoy® matrices. Once a metal matrix has been fabricated, multiple identical metal replicas from it become possible without the need to generate additional expensive and time consuming originals. These wear-resistant metal tools are then used to mass-produce microfluidic or optical components in various polymers. This is usually accomplished by stamping, embossing, injection or compression molding. The resulting micro- and nanofluidic devices are known as Lab-on-a-Chip (also referred to as micro-total-analytical systems or microTAS). They are designed to miniaturize analytical or bioanalytical (BioMEMS) techniques by integrating them into a microfabricated format.
NiCoForm fabricates NiColoy® electroforms from 4" (100 mm), 6" (150 mm), and 8" (200 mm) etched silicon and plastic originals (masters), with a submicron replication fidelity. Electroforms for molding applications usually range in thickness from .020" (0.5 mm) up to 0.25" (6 mm), and flatness of +/- .0005" (12.5 microns). Other sizes and tolerances are possible on request. Back sides of the electroforms are machined flat and parallel to the molding surfaces.
Common optical components that can be molded using electroformed tools include diffraction gratings, Fresnel lenses, diffusers, light distribution arrays, etc. Electroformed inserts for molding, embossing, casting and other plastic fabrication methods usually have flat machined back surfaces and can be produced from .010" to over .25" thick.
Optical NiColoy® replicas can also be used directly as metal optics - reflectors, shutters and mirrors, similar to the one depicted on the right. To enhance their optical performance and durability, high reflectivity inert coatings such as Gold, Silver, Rhodium, etc. can be applied to the surface.
Unlike optical and microfluidic electroforms, MEMS devices usually comprise several tightly adherent layers of electroformed (plated) metals on a variety of substrates. The electroformed layers become part of the finished device which often functions as a miniature contact, relay, spring or flexure, depending on the high elasticity of NiColoy® for its performance characteristics.