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Cowens, M. W.

Publications and source records attributed to Cowens, M. W..

Texas Instruments /TI/ 800 x 800 charge-coupled device /CCD/ image sensor

Very-large area high-performance CCD image sensors with 800 x 800 pixel format have been successfully fabricated and operated on the basis of a three-level polysilicon gate technology. They are thinned to 8 microns over the entire 12.2 x 12.2 mm active area, and are used in the rear illumination mode. The light transfer characteristic has a gamma value of 1.000 + or - 0.002 over most of the dynamic range. Analysis of the noise behavior shows that the device SNR is shot-noise-limited over most of the dynamic range. Simple on-chip signal processing can be performed using an integration well to noiselessly collect signal charge from multiple pixels prior to reading out the charge. A UV-sensitive phosphor has been applied to the chip, yielding a device capable of imaging at wavelengths from the vacuum UV to the near IR.

Blouke, M. M.↗

Ultraviolet /UV/ sensitive phosphors for silicon imaging detectors

The fluorescence properties of UV sensitive organic phosphors and the radiometric properties of phosphor coated silicon detectors in the VUV, UV, and visible wavelengths are described. With evaporated films of coronene and liumogen, effective quantum efficiencies of up to 20% have been achieved on silicon photodiodes in the vacuum UV. With thin films of methylmethacrylate (acrylic), which are doped with organic laser dyes and deposited from solution, detector quantum efficiencies of the order of 15% for wavelengths of 120-165 nm and of 40% for wavelengths above 190 nm have been obtained. The phosphor coatings also act as antireflection coatings and thereby enhance the response of coated devices throughout the visible and near IR.

Viehmann, W.↗

Ultraviolet downconverting phosphor for use with silicon CCD imagers

The properties and application of a UV downconverting phosphor (coronene) to silicon charge coupled devices are discussed. Measurements of the absorption spectrum have been extended to below 1000 A, and preliminary results indicate the existence of useful response to at least 584 A. The average conversion efficiency of coronene was measured to be approximately 20% at 2537 A. Imagery at 3650 A using a backside illuminated 800 x 800 CCD coated with coronene is presented.

Blouke, M. M.↗