A sub-fF capacitive fingerprint sensor with neighbor pixel difference sensing

Two High-Precision Proximity Capacitance CMOS Image Sensors with Large Format and High Resolution

“…Figure 20 shows the benchmarking of the developed proximity capacitance CMOS image sensors with other array and discrete capacitance sensors [ 6 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 26 ]. The developed sensors had a large pixel area and a higher resolution while achieving higher detection accuracy than those of other sensors.…”

“… Benchmark comparison with other sensors [ 6 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 26 ]: ( a ) comparison of detection precision and pixel area; ( b ) comparison of detection precision and pixel pitch and examples of target. …”

“…Unlike optical image sensors, these sensors can detect electrical connections as well as microstructures and minute irregularities on the surface of objects and distribution of substances inside organic, solid, and liquid materials. Because of these features, they are used in various applications such as wiring inspection for flat panel displays and printed circuit boards [ 6 , 7 , 8 ], fingerprint authentication [ 9 , 10 , 11 , 12 ], observation of cellular reaction processes [ 13 , 14 ], and so on. These applications require high detection precision of aF (10 −18 F) or lower, as well as the ability to capture a sufficiently large area and a clear image of minute targets.…”

[Invite Paper] High Accuracy High Spatial Resolution and Real-Time CMOS Proximity Capacitance Image Sensor Technology and its Applications

“…Among various types of image sensors, proximity capacitance image sensors detect twodimensional proximity capacitance information between sensors and targets. The proximity capacitance discrete sensors and image sensors have been developed and employed in various industrial and biometric applications, such as in fingerprint sensors [1][2][3][4] , humanmachine interface 5) , liquid level detection for manufacturing plants, capacitance manometer for gas pressure detection, non-destructive electrical capacitance tomography [6][7] , inspection equipment for flat panel display and printed circuit boards 8) . Furthermore, researches are actively conducted towards visualization and measurement of cell reactions in the biological and medical fields [9][10][11][12] .…”

CMOS-MEMS technologies for the applications of environment sensors and environment sensing hubs

“…Among these fabrication technologies, CMOS-MEMS approach exploits the standard commercial semiconductor process platforms to implement micro sensors and actuators, and hence the mature semiconductor technologies and supply chain can be leveraged to effectively reduce the time and efforts for commercialization. Numerous CMOS-MEMS devices have been demonstrated using different commercial platforms, for example, the tactile sensor [31], magnetic sensor [32] and accelerometer [33] from the TSMC (Taiwan Semiconductor Manufacturing Co., Taiwan) 2P4M (in this review: 'P' and 'M' respectively stand for 'Poly-Si' and 'Metal', '2P4M' means the process consisted of two poly-Si and four metal layers) standard process shown in figure 1(a), the gyroscope [34], microphones [35] and tactile sensors [36] from the TSMC 1P6M process displayed in figure 1(b), and the RF devices [37,38] and fingerprint sensors [39] from the UMC (United Microelectronics Co., Taiwan) 0.18 µm 1P6M CMOS process depicted in figure 1(c). By using the existing CMOS platforms, many environmental sensing chips have also been developed, which include sensors for the detection of temperature, pressure, IR, gas, PM 2.5 [40], etc.…”