Fine-Grained Defect Diagnosis for CMOL FPGA Circuits

Nanotechnology is an important technological alternative to overcome the limitations of complementary metal-oxide-semiconductor (CMOS) technology. Various circuit implementation methods based on nanotechnology have been proposed, and their most important characteristics are a high defect ratio and defect tolerance through circuit reconfiguration. CMOS-nanowire-MOLecular (CMOL) field-programmable gate array (FPGA) circuits are advanced logic circuit structures that combine the advantages of CMOS and nanotechnology. However, researches on defect diagnosis methods for the reconfiguration of CMOL FPGA circuits are barely conducted. In this paper, efficient circuit configuration methods for defect diagnosis of the CMOL FPGA circuits are proposed to address the problem. Also, diagnosis algorithms for both stuck-at open and stuck-at close defects are introduced. Experimental results show that with the proposed methods, diagnosis is possible for CMOL fabrics with up to 20% stuck-at open defects and 0.02% or more stuck-at close defects.