Novel technique for reliability testing of silicon integrated circuits

We propose a simple, inexpensive technique with high resolution to identify the weak spots in integrated circuits by means of a non-destructive photochemical process in which photoresist is used as the photon detection tool. The experiment was done to localize the breakdown link of thin silicon dioxide capacitors of 5 X 5 and 10 X 10 micrometer2 in sizes. Both positive and quasi-negative photoresists were employed. The resultant products are holes in the developed positive photoresist layer and mushroom- shaped spots in the quasi-negative one. Based on the photoresist decomposition energy dose, we could approximately calculate the light emitting power in the near UV range. Due to the proximity between the layer and the light source, the power is interpreted on a more accurate basis, which was a difficult task in previous research. The product sizes, dependent on the light emitting currents and exposure time, establish the core for a rough model that can be used for further application of this technique as a reliability analysis tool. One potential application is to detect and characterize regions of hot carriers on a VLSI circuit under operation for design improvement purpose.