The evolution of integrated circuit technology over the five decades resulted in scaling down the minimum feature size of a transistor from 10 μm to ~14 nm. The high-k dielectrics were identified as potential candidates to replace SiO2 from 2007 due to the large leakage current observed when scaling down SiO2. These materials captured the attention of many researchers and led them to focus on many emerging applications in addition to metal oxide semiconductor field effect transistors (MOSFET). In this thesis, two emerging applications of high-k dielectrics were investigated: (i) germanium based MOSFETs and (ii) high frequency high speed rectifiers for optical rectennas.