This paper is an extension of the current research being conducted at the US Army Aviation and Missile Research, Development and Engineering Center. The initial work for this research was presented at the 2004, 2005 and 2006 IEEE Aerospace Conferences in papers titled "Phased Arrays using Dual-Wafer Fabrication / High Integration Processes" (J.C. Rock, 2004), "Integration of Antenna Elements onto Semiconductor Substrates for use in Phased Arrays (J.C. Rock, 2005) "and "Semiconductor Substrates in Phased Arrays -Integration Issues, Challenges and Laboratory Results (J.C. Rock ,2006)". Early surveys of industry and academia to determine the state-of-the-art in phased array systems showed that the major barriers impinging upon continued wafer-level component integration (along with the radiating elements associated with the array) included heat dissipation and thermal management, packaging, shielding of radiation from micro-or nano-electronic circuitry, and quantification of any electromagnetic interactions between radiating elements and the semiconductor substrate. The main purpose of this current analysis is to quantify electromagnetic interactions through a study of the propagation characteristics of plane waves in semiconductor materials. For this paper, we examine the optimum pairing of substrate length and ion implantation doping for use in shielding other semiconductor devices by creating an electromagnetic evanescent area. This will be accomplished through simulation studies and verified in the laboratory using silicon as a sample substrate. An earlier study quantified electromagnetic interactions in bulk semiconductor materials and showed that as conductivity increased, the field decreased substantially as expected. That study is discussed here for clarity and expanded to include multilayer semiconductor wave propagation.