Micro-scale structures are becoming more popular and in demand in recent years in the world of science, technology, and manufacturing. Many are excited about the possibilities microfabrication has in creating electronic devices such as photonics and sensing equipment. Learn more about what microfabrication is in Precision Machining and the basic techniques that come along with this practice.
What is Microfabrication
Microfabrication is the underlying technology behind the design of integrated circuits (ICs), microsensors, inkjet printers, and flat panel displays, and also including some other electronics. Although it sounds complicated, the basic techniques and microstructures are fairly simple and straightforward. Micromachining takes place on a scale of 1 to 100 nm in size. Microfabrication is an all-encompassing term or phrase that includes all manufacturing activities involving building structures on a micrometer or even smaller scale.
One microfabrication technique that you should be aware of is lithography. It’s a technique that’s used to transfer a computer-generated pattern onto a substrate (i.e. silicon, glass). After the creation of the photomask, you can move forward with the lithography process. Following the deposit of the desired material on the substrate, the photolithography process begins with spin-coating the substrate with a photoresist.
One basic microfabrication technique is called etching. It’s when you chemically remove layers from the surface of a wafer during the manufacturing process. It usually is separated into two different classes including wet etching and plasma etching. When using ion beam etching, several solid-state laser and magnetic materials are etched.
Another basic technique used in microfabrication is thermal oxidation. In short, it works to produce a thin layer of oxide (typically silicon dioxide) on the surface of a wafer. It’s a technique that creates an oxidizing agent to diffuse into the wafer at a high temperature and then react with it. Silicon oxide makes silicon-based microfabrication very efficient. Another vital trait of a thermally grown oxide film is that it increases in thickness, more so than the portion of the silicon wafer used to produce the oxide.
Doping & Diffusion
Doping is yet another basic microfabrication technique that’s a necessary step in the process of precision manufacturing. Doping is the primary process used in the microelectronic industry to produce major components such as diodes and transistors. In microfabrication technologies, doping has supplementary and other applications like the formation of piezoresistors for mechanical transducers or the creation of etch stop-layers. In terms of microfabrication, diffusion is mostly used in the formation of, especially highly boron-doped regions. These are typically usually used as an etch stop in bulk micromachining.
To construct a microdevice, many processes must be performed and played out, continuously and in repetition, many times over. These are just some of the basic techniques used in the microfabrication process. However, there are others and the creation of products and small parts in precision manufacturing is much more intricate and involved. This at least gives you a general idea of what microfabrication is and the techniques that are used in fabricating miniature structures of micrometer scales and smaller.