Direct Detection of Low-Energy Electrons With a Novel CMOS APS Sensor

• Published in: IEEE transactions on electron devices Vol. 59; no. 12; pp. 3594 - 3600
• Main Authors: Xiaoping Zha, El-Gomati, M. M., Li Chen, Walker, C., Clark, A. T., Turchetta, R.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.12.2012; Institute of Electrical and Electronics Engineers
• Subjects: Active pixel sensors (APSs); Applied sciences; CMOS image sensors; CMOS integrated circuits; Design. Technologies. Operation analysis. Testing; Detectors; Electron beams; electron microscopy; Electronics; Exact sciences and technology; General equipment and techniques; Imaging devices; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Integrated circuits; Noise measurement; Photodiodes; Physics; Scanning electron microscopy; Scanning probe microscopes, components and techniques; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Sensors (chemical, optical, electrical, movement, gas, etc.); remote sensing; Scanning electron microscopy; Measurement sensor; CMOS image sensors; Electron beam; Electron microscopy; Smart pixels; Direct detection; Complementary MOS technology; Image sensor; Electron detection; Low-power electronics; Spatial resolution; Active pixel sensors (APSs)
• ISSN: 0018-9383; 1557-9646
• DOI: 10.1109/TED.2012.2219623

Direct detection of low-energy electrons (500-2000 eV) with a novel back-thinned CMOS active pixel sensor (APS) is reported in this paper. The sensor was installed in a JEOL 6400F scanning electron microscope to quantitatively test its linearity and spatial resolution by a focused electron beam. The obtained results show good linearity at electron beam energy values from 500 to 2000 eV. The full-width at half-maximum spatial resolution was around 2 pixels, a limit set by charge diffusion in the epilayer. These results show that this CMOS APS sensor is appropriate for low-energy electron detection providing the benefits of direct detection for many applications.