We present an antenna coupled non-resonant plasmawave CMOS detector operating at 502 GHz, with a PMOS load and NMOS stacked structure. The gates of the NMOS plasma wave FETs, which are located in the middle of the stack, in a differential structure, are connected to the voltage-maximum points of a patch antenna. It was found that the high-input impedance of the detector causes high responsivity as the loaded Q of the antenna is enhanced and because the resultant high-voltage swing at the input allows the detector to have high responsivity. High input impedance can be achieved via using the stacked structure in conjunction with a small input transistor and the sub-threshold bias. The responsivity of stacked structure was also affected by source-drain voltage in the plasma-wave FET and active load resistor by PMOS. Therefore, it was found that the responsivity is closely related to the product of the stacked structure, where is the bias current, is the voltage across the input NMOS plasma-wave FET and is the small signal resistance of the PMOS load parallel with plasma -wave FET channel resistance. The detector shows the higher response than a cold-FET detector by one order of magnitude.

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Neural recording systems have significantly progressed to provide an advanced understanding and treatment for neurological diseases. Flexible transistor‐based active neural probes exhibit great potential in electrophysiology applications due to their intrinsic amplification capability and tissue‐compliant nature. However, most current active neural probes exhibit bulky back‐end connectivity since the output is current, and the development of an integrated circuit for voltage output is crucial for near‐sensor signal processing at the abiotic/biotic interface. Here, inkjet‐printed organic voltage amplifiers are presented by monolithically integrating organic electrochemical transistors and thin‐film polymer resistors on a single, highly flexible substrate for in vivo brain activity recording. Additive inkjet printing enables the seamless integration of multiple active and passive components on the somatosensory cortex, leading to significant noise reduction over the externally connected typical configuration. It also facilitates fine‐tuning of the voltage amplification and frequency properties. The organic voltage amplifiers are validated as electrocorticography devices in a rat in vivo model, showing their ability to record local field potentials in an experimental model of spontaneous and epileptiform activity. These results bring organic active neural probes to the forefront in applications where efficient sensory data processing is performed at sensor endpoints.

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