New Process Development for Planar-Type CIC Tunneling Diodes

Abstract

A planar-type conductor-insulator-conductor tunneling diode is developed using a boiling water process for surface oxidation. First, microsized bow-tie patterns are transferred on a doped polysilicon layer using e-beam lithography. After reactive ion etching, the polysilicon bow-tie pattern has a very narrow knot between two triangles. Using a buffered oxide etchant (BOE) solution, hydrogen silsesquioxane patterns and native oxide layer are etched. The knot is oxidized by a boiling water oxidation process. By repeating the BOE etch and oxidation, the bow-tie patterns are transformed into tunneling diodes with a very thin oxide barrier separating two polysilicon conductors. We show that the resulting structures follow the Simmons tunneling current-voltage relationship after boiling. Moreover, a high sensitivity of 31 V −1 is achieved at a bias voltage of 80 mV.Index Terms-Bow-tie antenna, metal-insulator-metal (MIM) diode, optical antenna, surface plasmon, surface plasmon resonance (SPR), tunneling diode.

Graphene ballistic nano-rectifier with very high responsivity

“…The responsivity is determined by the output d.c. voltage divided by the input a.c. power (the a.c. voltage drop across S and D is measured simultaneously). The optimum intrinsic responsivity was measured to be 23,000 mV mW −1 , which is to the best of our knowledge, one of the highest in diode detectors to date 9 25 26 27 28 29 . In comparison, the previous BR based on low-mobility graphene on SiO 2 had a responsivity of just 67 mV mW −1 , >300 times lower 10 .…”

Numerical Analysis of MIM-Based Log-Spiral Rectennas for Efficient Infrared Energy Harvesting

“…Krishnan et al [20] characterized the performance of Ni-NiO-Cr/Au MIM structures at 2.5 GHz using a microstrip slot antenna. The authors of [14] and [25] reported that the utilization of polysilicon as the metallic material in planar type tunneling diodes enhanced their responsivity. Bean et al [13] coupled the Al-AlO x -Pt diode with a dipole antenna for IR rectification.…”

“…Similarly, the increase in the oxide thickness enhances the sensitivity of the diode due to the increase in the non-linear characteristics of the diode [4,8,10,23]. However, careful analysis of this increase in the oxide thickness is required as the slide increase in the thickness of the used oxide layer could drastically increase the diode's resistance, and thus impact the antenna-diode matching [4,8,13,22,25].…”

“…The sensitivity of the MIM diodes depends on the diode structure (symmetric or asymmetric), the metals that are used, the sandwiched oxide insulator(s), the contact area between the antenna's terminals, oxide thickness, and operating frequency [13,22,25]. Symmetrically structured diodes have the same metals on both sides of the oxide insulator [21,22,24] and vice versa for the asymmetric diode structures [4,8,10,11,13,14,20,23,25,26]. Besides this, as the rectifier has to be integrated with the optical nano-antenna, the value of its zero-bias resistance must be of the same order of magnitude as the designed antenna to ensure the efficient matching and maximum transfer of captured IR energy by the antenna terminal [1,4,6].…”

Analysis of the efficiency with which geometrically asymmetric metal–vacuum–metal junctions can be used for the rectification of infrared and optical radiations

“…1,2,[17][18][19][20][21] In practice, the junction biasing will typi-cally result from a laser beam whose energy is partially absorbed by a nanoantenna placed in series or integrated with the junction. [30][31][32][33][34][35][36] This makes these junctions useful for the development of high-speed electronics and for applications related to the harvesting of solar energy. 17,27 The rectification achieved by the junction will depend in turn on the possibility for electrons to cross the junction before the induced electric field changes sign.…”