Solution-Based PbS Photodiodes, Integrable on ROIC, for SWIR Detector Applications

• Published in: IEEE electron device letters Vol. 34; no. 5; pp. 662 - 664
• Main Authors: Heves, Emre, Ozturk, Cem, Ozguz, Volkan, Gurbuz, Yasar
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01-05-2013; Institute of Electrical and Electronics Engineers
• Subjects: Applied sciences; Colloidal quantum dots (CQD); Design. Technologies. Operation analysis. Testing; Electronics; Exact sciences and technology; General equipment and techniques; Imaging devices; infrared detectors; infrared image sensors; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Integrated circuits; Lead; Optoelectronic devices; photodetector; Photodiodes; Physics; Quantum dots; Schottky diodes; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Sensors (chemical, optical, electrical, movement, gas, etc.); remote sensing; Silicon; Substrates; High performance; Focal plane arrays; Quantum dot; Colloidal quantum dots (CQD); infrared detectors; Measurement sensor; Infrared detector; Film formation; Photodiode; Lead sulfide; Quantum yield; infrared image sensors; Photodetector; IV-VI compound; Optimization; Near infrared radiation; Response function; photodiodes; Integrated circuit; Optoelectronic device; Silicon; Thermal imaging; Image sensor
• ISSN: 0741-3106; 1558-0563
• DOI: 10.1109/LED.2013.2253756

Photodiodes, based on PbS colloidal quantum dots (CQD), are realized on both silicon substrates and the replicas of the read-out integrated circuits (ROICs) to demonstrate the first, fully integrated focal plane arrays. Careful optimization of PbS CQD film formation and ligand exchange process, together with optimized process steps, resulted in high performance, monolithically integrable photodiodes. High quantum efficiencies of 32% are achieved for photodiodes on Si substrates and high responsivities up to 5.73 A/W is achieved for photodiodes on ROIC replicas. These detectors achieved very high, normalized detectivities of 1.36 × 10 11 Jones and 1.42 × 10 12 Jones under 1 and 2-V reverse bias, respectively, that are close to conventional InGaAs short wave infrared detectors.