In this paper we present a time-gated single-photon avalanche diode (SPAD) array, the first of its kind to be integrated
with a newly developed time-resolved laser Raman spectrometer. Time-resolved Raman spectra from various highly
fluorescent minerals were successfully observed using our SPAD array; these spectra were obscured by an
overwhelming fluorescence background when measured using a traditional continuous wave green laser. The system has
photon detection efficiency (PDE) of 5 % at 5 V excess bias with on-chip microlenses. The dark count rate (DCR) of
this SPAD is 1.8 kHz at 5 V excess bias. However, thanks to the nanosecond scale time-gating, noise rate per frame is
effectively reduced to ~10-3 counts at 40 kHz laser repetition rate.
In this paper we present the methodology for making absolute quantum efficiency (QE) measurements from the vacuum
ultraviolet (VUV) through the near infrared (NIR) on delta-doped silicon CCDs. Delta-doped detectors provide an
excellent platform to validate measurements through the VUV due to their enhanced UV response. The requirements for
measuring QE through the VUV are more strenuous than measurements in the near UV and necessitate, among other
things, the use of a vacuum monochromator, and good camera vacuum to prevent chip condensation, and more stringent
handling requirements. The system used for these measurements was originally designed for deep UV characterization
of CCDs for the WF/PC instrument on Hubble and later for Cassini CCDs.
We present proof-of-concept results for a novel ultraviolet-sensitive, photon counting, solar blind detector that
has the potential for high QE in a compact low voltage, low power, unsealed design. We utilize a delta-doped
back-illuminated CCD to read out low energy electrons from a photocathode. In parallel, a new generation
of high-QE ultraviolet-sensitive GaN photocathodes is being developed with initial success using delta-doping
technology rather than cesiation. In this paper we present results with the new readout using a CsI test cathode,
which produces events at under 1000 V accelerating potential.
Next generation, space-based, Sun-Earth System remote sensing missions place severe challenges on focal plane technologies to achieve their science goals. Among these are high sensitivity over a broad spectral range, small pixel size, fast readout, radiation tolerance, low power consumption, photometric accuracy & stability, and scalable mosaic technology for constructing large focal plane mosaics. Our Jet Propulsion Laboratory, Lawrence Berkeley National Laboratory, University of Alabama in Huntsville collaboration has begun the development of an Advanced Broadband Imager (ABI) to address these challenges for future Sun Solar System Connection science missions. We describe here the development of the delta-doped, high-purity, p channel charge coupled devices, which form the heart of the ABI imager, and our plans for future development. The current technical readiness levels of ABI component technologies are TRL 2 to TRL 4. Our proposed development program envisions achieving TRL 5 within 3 years with flight validation in the context of an Earth Sun System Science mission occurring within 6 years via the Quiet-Sun Transition Region Explorer EUV Telescope (Q-STREET) rocket-borne observatory.