The main process starts with domestic electricians creating the circuit and determining its functions, and specifying the signals, inputs, results and currents needed. These electrical circuit specs are applied for electrical circuit design software, such as SPICE, and then imported into circuit layout programs, which are much like ones employed for computer aided design. This is essential for the layers to be defined for photomask production. The resolution of the circuits increases rapidly with every part of design, because the scale from the circuits at the beginning of the look process is already being measured in fractions of micrometers. Each step thus increases circuit density for a given area.

       The silicon wafers begin blank and pure. The circuits are made in layers in clean rooms. First, photoresistpatterns are photo-masked in micrometer detail onto the wafers' surface. The wafers will be exposed to short-waveultraviolet light and the unexposed areas are thus etched away and cleaned. Hot chemical vapors are deposited to the desired zones and baked in high temperature, which permeate the vapors in to the desired zones. These steps are often repeated 100s of times, depending on the complexity of the desired circuit and its connections.

      New processes to accomplish each of these steps with much better resolution as well as in improved ways emerge each year, with the result of constantly changing technology within the wafer fabrication industry. New technology result in more dense packing of minuscule surface features including transistors and micro-electro-mechanical systems . This increased density continues the popularity often reported as Moore's Law.