Evaluation of phase change materials for reconfigurable interconnects

Abstract

The possible use of programmable integrated circuit interconnect vias using an indirectly heated phase change material is evaluated. Process development and materials investigations are examined. Devices capable of multiple cycles between on/off states for reconfigurable applications have been successfully demonstrated in a standard CMOS-compatible technology. Building computer chips with these vias would create a new kind of field programmable gate array (FPGA), whereby the design can be reconfigured depending on its application. The phase change reprogrammable-via is nonvolatile, unlike SRAM-based technology. It also has a relatively low on-state resistance and occupies less real estate on the chip. As the "switches" are placed at the metallization level, it provides flexibility for the designer to place them. Programmable-via can operate at a relatively low voltage compared to FLASH-based technology. Similar to the case of antifuses, programmable-via interconnect structures are projected to be radiation hard. However, the most challenging part of implementation is the circuit design. Issues such as integration of materials and design with current tools need to be overcome. A lack of expert personnel in this area also makes the implementation of programmable-via FPGAs complicated. The market for FPGA is promising due to the attraction of the programmable logic market. An intellectual Property (IP) analysis indicates there exist a significant new space for exploration in this area. The best-suited business model is as a new start-up that demonstrates feasibility and develops intellectual property. The potential commercialization of such technology is also discussed. Although this concept is promising result, more research is needed to show the reliability and feasibility of such a technology in complex circuits. It will take some time before this approach can be considered for production.