Characterization Results of Teledyne DALSA High Bandwidth Matrix and Linear CMOS Device and Roadmap for Radiation Hard and High Resolution Area Devices – DALSA
– IT-K2 family of image sensors for colour imaging and X-ray products was described. The dual line 7um pixel have full well capacity if 30ke- while the single line pixels have a pitch of 3.5um.
– The FPN reported was less than 40DN, conversion gain of 0.126DN/e/line, noise floor of 12e-and dynamic range of 66dB, PRNU less than 10% and non-linearity of less than 2% between 10-90% saturation signal was reported.
– Over exposure detection circuit before CDS block was used to remove the overexposure artefacts.
High QE, Thinned Backside Illuminated 3e- RoN, Fast 700fps, 1760×1760 Pixels Wave Front Sensor Imager with highly parallel readout – ESO
– Imagers to image the natural guide star and laser guide star was described.
– A 4T rolling shutter (in chunks of 20 rows) with a pixel pitch of 24um, responsivity of >100uV/e-, Full well of 4ke-, Read noise of less than 3e- rms, QE of greater than 90% in the visible region and a lag of less than 0.1% was reported.
– The desired dimension of the imager is 50 x 60mm2. One serious problem with huge imagers would be to drive the clocks over such huge length. The presenter presented an idea of using primary and secondary clocks and synchronously switching ON/OFF the stitched channels to solve the clocking problem over long distance.
L2CMOS Image Sensor for Low light Vision – e2v
– Light from night sky provides photons mostly in the NIR region of the spectrum thus QE improvement in this region would be very beneficial.
– QE improvement by deep depletion is proposed.
– Pixel pitch of 5.3um, Full well of 50ke- and total noise of 3.1e- rms (ADC noise of 1.5e-, Pixel SF noise 2.2e-) at 25 frames per second was reported. A surface channel source follower was used.
– Some pictures were shown at 0.0011 lux (starlight) at 20fps. Interesting pictures and video shown. Very noisy but interesting.
– Because of the deep depletion, diffuse electrons are also collected thus images formed are less focussed, a side effect clearly seen in the pictures shown.
Fast Response, Low Noise, Multiple Shutter, Non-destructive readout Line Sensor for Spectroscopy Applications based on lateral drift field photodiode principle – Fraunhofer
– The LDFD (lateral drift field photodiode) principle was used in optical excitation spectroscopy. The photomultipliers has been used in those applications primarily due to its high response time (nearly 100ns).
– The principle of LDFD is a concept similar to CCD and p+ pinning. The n-well doping concentration is increased in the direction of the sense node.
– 10um pixel pitch was shown, it was mentioned that work on 5um pitch is in progress.
– A dark current of 41pA/cm2 and a response time of 3.5us are shown. The fill factor is claimed to be 100% which is not true as a channel stop of 2um is used (good catch from the audience).
ESA supported development in CMOS imaging sensors – ESA-ESTEC
– An overview of image sensor programs with ESA was presented.
– Back side illuminated thinned hybrid image sensors were developed together with imec. The sensors specifications were read noise of 25e-, full well of 0.4Me-, QE of greater than 80% over 270-400nm, pixel pitch of 20um with an array size of 1024×1024 was reported.
– Back side illuminated thinned monolithic image sensors were developed together with CMOSIS. The reported figures for the desired imager were pixel pitch of 15-25um, full well of 0.5Me-, QE of greater than 70% over 350-800nm and a read noise of 50e- rms. The kick off will be in Jan. 2012.
CMOS Image sensor for lunar mission – CMOS Sensor Inc
– Two imagers for lunar mission, a line sensor with 4000 line elements and an array sensor with a 256×512 array was presented.
– The line sensor had a pitch of 7um, 12 bit resolution, DR of 123.2dB (the DR was calculated using the output of destructive load over non-destructive load, if the noise is used then the sensor would have a DR of 50dB with a noise of 68DN) and non-linearity of less than 0.1%.
– The array sensor used a pixel pitch if 50um, 12 bit ADC and had a non-linearity of less than 0.5%.
– Beautiful pictures of moon and earth were shown.
– The FPN and dark count for linear sensor was shown to increase after TID of 100krad.
High Speed BSI CMOS Image Sensor for space applications with 1.1Me- full well capacity and 28e- rms read noise – BAE Systems Imaging solutions
– A hyper spectral imaging within the project EnMap was presented.
– A pixel pitch of 24um, 5T pinned photodiode, full well of 1.1Me-, spectral range of 420nm-980nm, DR of greater than 1500:1, read noise less than 70e- for high gain and less than 200e- for low gain TID of 14.51 with a power less than 2W is desired.
– The QE was shown to be 85% at 600nm, a conversion gain of 1uV/e-, a dark current of 150e-/pixel/ms at 293K and a read noise of 27e- when operated in rolling shutter mode while 44e- when operated in global shutter and a 50% MTF at Nyquist was shown to be obtained.
– The single event upset for particle beams of 1.6MeV and 42.5eV was shown to cause an increase in the readout noise by nearly 10% while the conversion gain and the dark signal were not affected much. The non-linearity for high gain increased marginally while for low gain it was minimum.
– Image lag is important for 24um pixel pitch, and it was raised in the question and answer session. The image lag is kept low by segmenting the pixel into a mosaic kind of structure. This keeps the overall image lag low.
Characterization of a digital TDI CMOS demonstrator for high resolution earth observation –CMOSIS
– A TDI demonstrator for high resolution earth observation applications was presented.
– 50TDI stages with a pixel pitch of 13um and 1500 columns (to be increased to 6000 columns) with a 10 bit cyclic ADC as shown. The readout time was around 1.3us, with a 70uV/e- conversion gain, 3e- read noise, full well of 130ke-, good linearity, no image lag and no “black sun” effect observed while a QE if 55% at 550nm was reported.
– It was reported that column ADC reaching a speed of 1.4MPS caused stability problems, may be due to the reference voltage instability.
Written by M. Sarkar
7-12-2011