Structurally, an MIM diode is a very thin layer of insulator sandwiched between two metal electrodes. Owing to the tunneling based conduction mechanism it facilitates ultra-fast switching speed, desirable for many of the high frequency applications. However, due to thin insulator design considerations and underneath conduction mechanism, they normally do not exhibit diode like behavior. Therefore, the successful implementation of the diode in these applications demands highly non-linear and asymmetric current-voltage characteristics. This necessitates the consideration of design aspects of diode prior to its actual fabrication. In this paper the various design aspects of MIM diode is studied and their influence on the diode's figures of merit is investigated.