Here we report on comprehensive investigations of receiving antenna characteristics of monolithically integrated field effecttransistor-based terahertz detectors with patch antennas which are often used for a variety of applications [1,2]. Devices are implemented using a standard 65-nm CMOS process technology. Furthermore, we investigate a set of devices coupled to the antenna with same geometrical parameters but connected to a device with a different channel length thus allowing to vary the impedance of antenna load not only through the bias voltage. The directivity values of antennas were determined by measuring the angle dependence of rectified voltage as a function of the tilt in E- and H-planes which are presented in Fig. 1 and through the thorough comparison with the results of electromagnetic simulations using CST software. Considering the amount of input radiation power impinging to the determined effective area of the detector, we report a room-temperature cross-sectional noise-equivalent power of 17.1 pW/√Hz at the resonant frequency of 0.62 THz. This value represents the state of the art for electronic detectors operating at room temperature in this frequency range
