The fabrication of a full metal AFM probe and its applications for Si and InP device analysis

Pyramidal metal tips which are fixed to a silicon cantilever have proven to be very powerful probe tips in electrical Atomic Force Microscopy (AFM). Although silicon is currently the cantilever material of choice for most applications, solid metal cantilevers are an interesting alternative due to their higher electrical conductivity and a more simplified fabrication procedure. Therefore, we have developed a process scheme for such full metal probes and evaluated them in AFM. This paper discusses the fabrication scheme in detail and presents first results concerning the application of the fabricated probes for semiconductor device analysis. Our experiments clearly show that operational full metal probes can be made on a large scale in a 150 mm silicon wafer technology. Using the optimized process, full metal probes can be fabricated which can compete in contact-mode AFM with pyramidal metal tips fixed to a silicon cantilever. Our work is currently focussing on further improvement of batch reproducibility.