Impact of Custom Interconnect Masks on Cost and Performance of Structured ASICs

As process technology scales, the design effort and Non-Recurring Engineering (NRE) costs associated with the development of Integrated Circuits (ICs) is becoming extremely high. One of the main reasons is the high cost of preparing and processing IC fabrication masks. The design effort and cost can be reduced by employing Structured Application-Specific ICs (Structured ASICs). Structured ASICs are partially fabricated ICs that require only a subset of design-specific custom masks for their completion. In this dissertation, we investigate the impact of design-specific masks on the area, delay, power, and die-cost of Structured ASICs. We divide Structured ASICs into two categories depending on the types of masks (metal and/or via masks) needed for customization: Metal-Programmable Structured ASICs (MPSAs) that require custom metal and via masks; and Via-Programmable Structured ASICs (VPSAs) that only require custom via masks. We define the metal layers used for routing that can be configured by one or more via, or metal-and-via masks as configurable layers. We then investigate the area, delay, power, and cost trends for MPSAs and VPSAs as a function of configurable layers.