Detection of Microwave Signals Using PtSi/Porous Si Schottky Diode

Background: In this paper, detection of microwave radiations at room temperature using PtSi Schottky junction sensors is studied. This is made possible by fabricating a porous substrate over which the PtSi electrode was deposited. N-type Si substrates are made porous and Pt is electrochemically deposited into the pores. Methods: Pt is annealed and the resulting PtSi/porous Si Schottky junction exhibits a breakdown type behavior at its reverse bias mode. The magnitude of the breakdown voltage depends on several factors. This breakdown voltage is sensitive to microwave radiations. When the sensor receives a microwave radiation, its breakdown voltage decreases based on the magnitude of the radiation. The sensor is highly sensitive to the power of microwave radiations even in mW range. Conclusion: The Schottky diode sensor is almost insensitive to the signal frequency in the frequency range studied in this investigation. The best responsivity is obtained for the signal with the guide wavelength of 4.8702 cm. Instead of a coplanar waveguide (CPW), a rectangular waveguide is used in the current investigation. This eliminates the need for complicated impedance matching circuits.