Provided is a pad layout structure of a semiconductor chip capable of preventing lead-broken problems when packaging the semiconductor chip with a high aspect ratio in a tape carrier package. The cathode space is supplied with an oxygen-containing gas, and the anode space is supplied with a hydrogen-containing gas. The transmitter operates according to a first clock having a first clock rate, and the receiver operates according to a second clock having a second clock rate. The first photodiode is more sensitive to light having wavelengths between 400 nm and 500 nm than the second photodetector. Thus, by combining the hierarchical extraction with an intelligent connectivity technique, an electromigration analysis of a VLSI microelectronic design may be accomplished within the limitations of the analysis tools that is more accurate than previous electromigration analysis techniques. No threads or torque specifications are required.