Title
Active Terahertz Imaging Using Schottky Diodes in CMOS: Array and 860-GHz Pixel
Abstract
Schottky-barrier diodes (SBD's) fabricated in CMOS without process modification are shown to be suitable for active THz imaging applications. Using a compact passive-pixel array architecture, a fully-integrated 280-GHz 4 × 4 imager is demonstrated. At 1-MHz input modulation frequency, the measured peak responsivity is 5.1 kV/W with ±20% variation among the pixels. The measured minimum NEP is 29 pW/Hz1/2. Additionally, an 860-GHz SBD detector is implemented by reducing the number of unit cells in the diode, and by exploiting the efficiency improvement of patch antenna with frequency. The measured NEP is 42 pW/Hz1/2 at 1-MHz modulation frequency. This is competitive to the best reported performance of MOSFET-based pixel measured without attaching an external silicon lens (66 pW/Hz1/2 at 1 THz and 40 pW/Hz1/2 at 650 GHz). Given that incorporating the 280-GHz detector into an array increased the NEP by ~ 20%, the 860-GHz imager array should also have the similar NEP as that for an individual detector. The circuits were utilized in a setup that requires neither mirrors nor lenses to form THz images. These suggest that an affordable and portable fully-integrated CMOS THz imager is possible.
Year
DOI
Venue
2013
10.1109/JSSC.2013.2269856
J. Solid-State Circuits
Keywords
Field
DocType
imaging,compact passive pixel array architecture,frequency 1 mhz,sbd detector,image sensor,cmos image sensors,imager array,frequency 860 ghz,lens-less,nep,detector,schottky barrier diode,responsivity,microstrip antennas,terahertz wave detectors,silicon,on-chip patch antenna,schottky diodes,si,active terahertz imaging,elemental semiconductors,integrated cmos thz imager array,modulation frequency,frequency 280 ghz,mosfet,terahertz,cmos,lenses,terahertz wave imaging,unit cell,mosfet-based pixel measurement,schottky barriers,sensor arrays,patch antenna,lens
Image sensor,Responsivity,Computer science,Diode,Optics,Electronic engineering,CMOS,Terahertz radiation,Schottky diode,Frequency modulation,Optoelectronics,Detector
Journal
Volume
Issue
ISSN
48
10
0018-9200
Citations 
PageRank 
References 
20
2.10
3
Authors
7
Name
Order
Citations
PageRank
Ruonan Han115227.20
Yaming Zhang2499.92
Young-Wan Kim3345.86
Dae Yeon Kim4325.11
Hisashi Shichijo5283.96
Ehsan Afshari632536.65
Kenneth K. O724942.87