Hammam Elabd

Schottky-Barrier Infrared Charge-Coupled Device Focal Plane Arrays

Recent development of high-performance Pd2Si and PtSi Schottky-barrier IR-CCD image sensors make these monolithic focal plane arrays attractive for many SWIR and thermal imaging applications. PtSi Schottky-barrier detectors operated at 80K have quantum efficiency of several percent in the 3 to 5 μm spectral range and cut-off wavelength of about 6.0 μm. Pd2Si Schottky-barrier detectors operated between 120 and 140K have cut-off wavelength of 3.6 μm and quantum efficiency in the range of 1.0 to 8.0% in the SWIR band. High-quality thermal imaging was achieved with a 64x128-element PtSi Schottky-barrier IR-CCD imager in a TV compatible IR camera operated with 60 frames per second. This paper reviews the Schottky-barrier IR-CCD technology developed at RCA. A model for photoyield of Schottky-barrier detectors (SBDs) is reviewed and compared with experimen-tal data. The architecture and design trade-offs of the SBD IR-CCD imagers are discussed. Also included is a discussion of the quantum efficiency requirements for staring thermal imagers and the performance achievable with the Schottky-barrier IR-CCD arrays.

(Invited) “High-Performance Schottky-Barrier IR-CCD Image Sensors”

High-performance PtSi and Pd2Si Schottky-barrier IR-CCD image sensors were developed with 32×63 and 64×128 elements. PtSi Schottky-barrier detectors (SBDs) operated at 80 K have quantum efficiency of several percent in the 3 to 5 µm spectral range and cut-off wavelength of about 6.0 µm. Pd2Si SBDs operated between 120 and 140 K have cut-off wavelength of 3.6 µm and quantum efficiency in the range of 1.0 to 8.0% in the 1.0 to 2.5 µm band. High quality thermal imaging has been demonstrated with a 64×128-element PtSi Schottky-barrier IR-CCD imager in a TV compatible IR camera operated with 60 frames per second. Also SWIR reflective infrared imaging of very good quality was achieved with the Pd2Si Schottky-barrier IR-CCD image sensor.

Silicon Based Schottky Barrier Infrared Sensors For Power System And Industrial Applications

Schottky barrier infrared charge coupled device sensors (IR-CCDs) have been developed. PtSi Schottky barrier detectors require cooling to liquid Nitrogen temperature and cover the wavelength range between 1 and 6 μm. The PtSi IR-CCDs can be used in industrial thermography with NEAT below 0.1°C. Pd Si-Schottkybarrier detectors require cooling to 145K and cover the spectral range between 1 and 3.5 μm. 11d2Si-IR-CCDs can be used in imaging high temperature scenes with NE▵T around 100°C. Several high density staring area and line imagers are available. Both interlaced and noninterlaced area imagers can be operated with variable and TV compatible frame rates as well as various field of view angles. The advantages of silicon fabrication technology in terms of cost and high density structures opens the doors for the design of special purpose thermal camera systems for a number of power aystem and industrial applications.

Solid-State Infrared Imaging

Publisher Summary This chapter discusses the solid-state infrared (IR) imaging. IR imaging is the remote sensing and display of the spatial and time variations in the intensity of infrared radiation emitted and reflected from a scene. Thus, an IR imaging system is similar to closed-circuit TV, producing a video signal to be displayed on a monitor and fed to other signal-processing or control circuits. Variations in brightness across the displayed image are usually used to represent temperature variations across the scene. The IR spectrum lies between the visible and microwave bands of electromagnetic radiation and extends between 0.75 and 1000 μm. IR imaging systems for military, industrial, geological, and medical applications utilize the available atmospheric transmission windows in the IR band. The development of IR imaging systems using solid-state focal-plane arrays (FPAs) is being pursued intensively in several laboratories and represents a major recent interest of the IR community. Solid-state FPAs promise to reduce system cost and complexity considerably and to improve the performance and extend the scope of applications. The key issue in the development of solid-state IR-FPAs is how to achieve an array with high spatial resolution and very low minimum resolvable temperature. This requires large numbers of very sensitive IR detectors or pixels with very uniform photo-response and readout circuits and sufficiently large signal-to-noise ratios to approach background-limited performance (BLIP).