Integrated Circuits or semiconductor devices are fabricated through a multi-step process of photolithography. The lithography is accomplished by shining light (may be UV or other wavelengths) through optical ‘masks’ that generate patterns on the silicon wafer. These patterns undergo additional process steps such as diffusion and etching to create the various elements of an IC including: transistors, resistors, capacitors, switches, logic elements, memories, wiring metal and interconnect vias. The complete set of photolithographic masks are often referred to as a mask set.
An IC mask set can contain 20 to 30 photolithographic masks and required 30 to 40 processing steps at the foundry. On average, each processing step can take 1.5 days at the fab. In practice, the early processing steps (diffusion layers) take longer to process than the later metal layers. Triad has developed patented Agile ASIC technology that allows for analog, digital and mixed-signal circuits to be changed and interconnected by making a single mask layer change. By changing only the via layer between to routing fabric layers complex circuit changes can be realized in less than two days of foundry processing. The complex, lengthy process of 30 to 40 lithographic steps is reduced down to a via-layer change. This approach allows for rapid prototyping, low-risk and rapid design revision and highly cost-effective silicon usage for high-volume cost-optimized applications.