Temperature dependence of the modulation of electrical linewidth of single-crystal critical dimension artifacts

Single-crystal critical dimension (CD) test structures for reference material applications, with features defined using lattice-plane selective etching, are under development at NIST. The materials are intended to eliminate methods divergence between various types of metrology tools. Initial electrical measurements suggest that there are surface depletion effects that cause the electrical CD (ECD) measurements to underestimate what we think is the actual physical linewidth. In this paper, electrical measurements of these test structures are performed at several temperatures to determine whether such surface depletion effects cause underestimation of the CD.