Accurate determination of ultra-shallow junction sheet resistance with a non-penetrating four point probe

An accurate method to measure the four point probe (4pp) sheet resistance (R_S) of USJ Source-Drain structures is described. The new method utilizes Elastic Material gate (EM-gate) probes to form non-penetrating contacts to the silicon surface. The probe design is kinematic and the force controlled to ensure elastic deformation of the probe material. The probe material is selected so that large direct tunneling (DT) currents can flow through the native oxide thereby forming a low impedance contact. In this paper, the new 4pp will be demonstrated on a variety of implanted USJ structures.