NONCONTACT VLSI IMAGING USING A SCANNING ELECTRIC-POTENTIAL MICROSCOPE

We describe the design and use of a novel scanning microscope which de tects changes in electric potential above a surface. We demonstrate th at this can be employed to image integrated circuits of considerable c omplexity in various modes of operation and at a spatial resolution of similar or equal to 1 mu m. We discuss the advantages of applying thi s imaging technique to the non-invasive evaluation of very large scale integrated circuits and consider possible limits to its resolution an d sensitivity in this role.