Hybrid THz imaging detector with vertical antenna and sub-pixel suspended MEMS thermal sensor and actuator

摘要

A THz radiation detector comprising a vertical antenna separated from a suspended platform by an isolating thermal air gap for concentrating THz radiation energy into a smaller suspended MEMS platform upon which a thermal sensor element is located. THz photon energy is converted into electrical energy via a thermally isolated air gap between plates of a coupling capacitor that couples energy from the antenna to the thermal sensor. The capacitor plates used for capacitive coupling of the received signal realize an electro-static actuator whereby the application of a DC bias varies the coupling capacitor gap. The DC bias causes the actuator to pull the suspended platform close to the antenna to reduce the capacitive gap, increasing the coupling capacitance, to touch the antenna array thus quickly discharging the heat induced in the sensor platform or to perform advanced readout operations, such as amplitude modulation and correlated double sampling.

主权项

1. A terahertz (THz) detector assembly, comprising:
a first dielectric substrate; an antenna array fabricated on said first substrate, said antenna array including a first capacitive plate portion; a second dielectric substrate; a sensor array constructed on said second dielectric substrate, said sensor array comprising a suspended platform including a second capacitive plate portion and a thermal sensor, said sensor array operative to transfer THz energy received by said antenna array to an electrical load via capacitive coupling and to convert the heat generated by said load to an electrical signal, wherein said capacitive coupling provides thermal isolation between said antenna array and said sensor array, and wherein said suspended platform is suspended by one or more holding arms connected to said second dielectric substrate, the one or more holding arms acting as springs allowing said suspended platform to move; and wherein said assembly is implemented by vertically joining said antenna array to said sensor array so as to establish one or more coupling capacitors made up of the capacitive plate portion of said antenna array and the capacitive plate portion of said sensor array.