The Naval Research Laboratory is developing next generation CMOS imaging arrays for the Solar Orbiter and Solar
Probe Plus missions. The device development is nearly complete with flight device delivery scheduled for summer of
2013. The 4Kx4K mosaic array with 10micron pixels is well suited to the panoramic imaging required for the Solar
Orbiter mission. The devices are robust (<100krad) and exhibit minimal performance degradation with respect to
radiation. The device design and performance are described.
The SoloHI instrument for the ESA/NASA Solar Orbiter mission will track density fluctuations in the inner
heliosphere, by observing visible sunlight scattered by electrons in the solar wind. Fluctuations are associated with
dynamic events such as coronal mass ejections, but also with the “quiescent” solar wind. SoloHI will provide the
crucial link between the low corona observations from the Solar Orbiter instruments and the in-situ measurements
on Solar Orbiter and the Solar Probe Plus missions. The instrument is a visible-light telescope, based on the
SECCHI/Heliospheric Imager (HI) currently flying on the STEREO mission. In this concept, a series of
baffles reduce the scattered light from the solar disk and reflections from the spacecraft to levels below
the scene brightness, typically by a factor of 10<sup>12</sup>. The fluctuations are imposed against a much brighter
signal produced by light scattered by dust particles (the zodiacal light/F-corona). Multiple images are
obtained over a period of several minutes and are summed on-board to increase the signal-to-noise ratio
and to reduce the telemetry load. SoloHI is a single telescope with a 40⁰ field of view beginning at 5°
from the Sun center. Through a series of Venus gravity assists, the minimum perihelia for Solar Orbiter will
be reduced to about 60 Rsun (0.28 AU), and the inclination of the orbital plane will be increased to a
maximum of 35° after the 7 year mission. The CMOS/APS detector is a mosaic of four 2048 x 1930
pixel arrays, each 2-side buttable with 11 μm pixels.
This paper is a continuation of past papers written on fundamental performance differences of scientific CMOS and
CCD imagers. New characterization results presented below include: 1). a new 1536 × 1536 × 8μm 5TPPD pixel CMOS
imager, 2). buried channel MOSFETs for random telegraph noise (RTN) and threshold reduction, 3) sub-electron noise
pixels, 4) 'MIM pixel' for pixel sensitivity (V/e-) control, 5) '5TPPD RING pixel' for large pixel, high-speed charge
transfer applications, 6) pixel-to-pixel blooming control, 7) buried channel photo gate pixels and CMOSCCDs, 8)
substrate bias for deep depletion CMOS imagers, 9) CMOS dark spikes and dark current issues and 10) high energy
radiation damage test data. Discussions are also given to a 1024 × 1024 × 16 um 5TPPD pixel imager currently in
fabrication and new stitched CMOS imagers that are in the design phase including 4k × 4k × 10 μm and 10k × 10k × 10
um imager formats.
A high performance prototype CMOS imager is introduced. Test data is reviewed for different array formats that utilize
3T photo diode, 5T pinned photo diode and 6T photo gate CMOS pixel architectures. The imager allows several readout
modes including progressive scan, snap and windowed operation. The new imager is built on different silicon substrates
including very high resistivity epitaxial wafers for deep depletion operation. Data products contained in this paper focus
on sensor's read noise, charge capacity, charge transfer efficiency, thermal dark current, RTS dark spikes, QE, pixel
cross- talk and on-chip analog circuitry performance.
New applications for ultra-violet imaging are emerging in the fields of drug discovery and industrial inspection. High throughput is critical for these applications where millions of drug combinations are analyzed in secondary screenings or high rate inspection of small feature sizes over large areas is required. Sarnoff demonstrated in1990 a back illuminated, 1024 X 1024, 18 um pixel, split-frame-transfer device running at > 150 frames per second with high sensitivity in the visible spectrum. Sarnoff designed, fabricated and delivered cameras based on these CCDs and is now extending this technology to devices with higher pixel counts and higher frame rates through CCD architectural enhancements. The high sensitivities obtained in the visible spectrum are being pushed into the deep UV to support these new medical and industrial inspection applications. Sarnoff has achieved measured quantum efficiencies > 55% at 193 nm, rising to 65% at 300 nm, and remaining almost constant out to 750 nm. Optimization of the sensitivity is being pursued to tailor the quantum efficiency for particular wavelengths. Characteristics of these high frame rate CCDs and cameras will be described and results will be presented demonstrating high UV sensitivity down to 150 nm.