Status of Uncooled Infrared Detector Technology at ULIS, France

The high level of accumulated expertise by ULIS and CEA/LETI on uncooled microbolometers made from amorphous silicon enables ULIS to develop uncooled IRFPA with 17 µm pixel-pitch to enable the development of small power, small weight and power (SWaP) and high performance IR systems. Key characteristics of amorphous silicon based uncooled IR detector is described to highlight the advantage of this technology for system operation. A full range of products from 160 x 120 to 1024 x 768 has been developed and we will focus the paper on the ¼ VGA with 17 µm pixel pitch. Readout integrated circuit (ROIC) architecture is described highlighting innovations that are widely on-chip implemented to enable an easier operation by the user. The detector configuration (integration time, windowing, gain, scanning direction), is driven by a standard I²C link. Like most of the visible arrays, the detector adopts the HSYNC/VSYNC free-run mode of operation driven with only one master clock (MC) supplied to the ROIC which feeds back pixel, line and frame synchronisation. On-chip PROM memory for customer operational condition storage is available for detector characteristics. Low power consumption has been taken into account and less than 60 mW is possible in analogue mode at 60 Hz. A wide electrical dynamic range (2.4V) is maintained despite the use of advanced CMOS node. The specific appeal of this unit lies in the high uniformity and easy operation it provides. The reduction of the pixel-pitch turns this TEC-less ¼ VGA array into a product well adapted for high resolution and compact systems. Noise equivalent temperature difference (NETD) of 35 mK and thermal time constant of 10 ms have been measured leading to 350 mK.ms figure of merit. We insist on NETD trade-off with wide thermal dynamic range, as well as the high characteristics uniformity and pixel operability, achieved thanks to the mastering of the amorphous silicon technology coupled with the ROIC design. This technology node associated with advanced packaging technique, paves the way to compact low power system.Defence Science Journal, 2013, 63(6), pp.545-549, DOI:http://dx.doi.org/10.14429/dsj.63.5753

Serial monitoring of pancreatic stone protein for the detection of sepsis in intensive care unit patients with complicated abdominal surgery: A prospective, longitudinal cohort study.

The objective of this study was to assess the performance of pancreatic stone protein (PSP) monitoring for the detection of sepsis, prediction of outcome and distinction between bacterial and fungal infections in intensive care unit (ICU) patients with complicated abdominal surgery. In this prospective multicenter cohort study, patients with complicated abdominal surgery had serial PSP measurements during their ICU stay. Infectious episodes were classified as bacterial, fungal or mixed. PSPmax (maximal PSP value within 48 h of the diagnosis of infection) and ΔPSP (difference between PSPmax and the preceding PSP value) were used for analyses. PSPmax was obtained for 118 infectious episodes (68 patients). ΔPSP was available for 73 episodes (48 patients). Both PSPmax and ΔPSP were significantly higher in patients with sepsis and in patients with a fatal outcome. A PSPmax ≥124 ng/ml and a ΔPSP ≥34 ng/ml could detect sepsis with a sensitivity/specificity of 84%/54% and 69%/76%, respectively. There was no significant difference of PSPmax or ΔPSP between patients with bacterial/mixed versus fungal infections. Serial PSP monitoring may be an additional tool for the early detection of sepsis in patients with complicated abdominal surgery who are at high risk of severe infections

Phonons-defects interactions in CdTe

A study of electrically inactive defects has been performed on CdTe single crystals by two different experimental techniques : • the low temperature thermal conductivity measurement. It has been used as a tool to study crystal defects, such as clusters, stacking faults or point defects ; • the X ray topography. It completes the first method in showing large aggregates (resolution ≃ 1 μm), dislocation arrays or structural defects. The following observations regarding the experimental results are worth noting. CdTe crystals (undoped, Cl or In doped) have been grown by melting zone or THM. Microprecipitates are found in all CdTe crystals. The concentration varies from 1014 up to 1015 cm-3 and the mean diameter reaches 100 Å or more. This concentration is independant on the doping level and on the crystal growth process. The presence of such a precipitation is probably associated with the chemical and thermal growth conditions of the crystals. The K( T) curves fit by the Callaway phenomenological model indicates a point defect concentration of about 1018 cm-3. The isotopical mass deviation introduces only a concentration of 7 × 1017 cm -3. The excess is ascribed to several origins such as nonstoichiometry in CdTe, doping, chemical impurities or VCd. In X-ray topography large precipitates appear only in crystals not intentionally doped and melting zone purified, or in CdTe : Cl. No correlation is found between large and micro precipitates. Dislocations with atmosphere appear also with a low concentration of about 104 cm-2.Les défauts électriquement inactifs dans CdTe ont été mis en évidence par deux méthodes : • conductivité thermique à basse température, • topographie X. Dans tous les matériaux étudiés, créés par T. H. M. ou fusion de zone, non dopés, dopés au chlore et à l'indium, des microprécipités ont pu être étudiés. Leur concentration, déduite des mesures de conductivité thermique par un calcul basé sur la méthode de Callaway, est comprise entre 1014 et 1015 cm -3 et leur diamètre moyen supérieur ou égal à 100 A. Cette concentration est indépendante du taux de dopage et de la méthode d'élaboration. Des précipités beaucoup plus grands (1 μm) apparaissent en topographie X sur les cristaux non dopés et purifiés par fusion de zone ainsi que sur les matériaux dopés au chlore. Il n'y a pas de corrélation entre ces défauts et les microprécipités

Status of Uncooled Infrared Detector Technology at ULIS, France

The high level of accumulated expertise by ULIS and CEA/LETI on uncooled microbolometers made from amorphous silicon enables ULIS to develop uncooled IRFPA with 17 µm pixel-pitch to enable the development of small power, small weight and power (SWaP) and high performance IR systems. Key characteristics of amorphous silicon based uncooled IR detector is described to highlight the advantage of this technology for system operation. A full range of products from 160 x 120 to 1024 x 768 has been developed and we will focus the paper on the ¼ VGA with 17 µm pixel pitch. Readout integrated circuit (ROIC) architecture is described highlighting innovations that are widely on-chip implemented to enable an easier operation by the user. The detector configuration (integration time, windowing, gain, scanning direction), is driven by a standard I²C link. Like most of the visible arrays, the detector adopts the HSYNC/VSYNC free-run mode of operation driven with only one master clock (MC) supplied to the ROIC which feeds back pixel, line and frame synchronisation. On-chip PROM memory for customer operational condition storage is available for detector characteristics. Low power consumption has been taken into account and less than 60 mW is possible in analogue mode at 60 Hz. A wide electrical dynamic range (2.4V) is maintained despite the use of advanced CMOS node. The specific appeal of this unit lies in the high uniformity and easy operation it provides. The reduction of the pixel-pitch turns this TEC-less ¼ VGA array into a product well adapted for high resolution and compact systems. Noise equivalent temperature difference (NETD) of 35 mK and thermal time constant of 10 ms have been measured leading to 350 mK.ms figure of merit. We insist on NETD trade-off with wide thermal dynamic range, as well as the high characteristics uniformity and pixel operability, achieved thanks to the mastering of the amorphous silicon technology coupled with the ROIC design. This technology node associated with advanced packaging technique, paves the way to compact low power system.Defence Science Journal, 2013, 63(6), pp.545-549, DOI:http://dx.doi.org/10.14429/dsj.63.5753

Personalized cancer vaccine strategy elicits polyfunctional T cells and demonstrates clinical benefits in ovarian cancer.

T cells are important for controlling ovarian cancer (OC). We previously demonstrated that combinatorial use of a personalized whole-tumor lysate-pulsed dendritic cell vaccine (OCDC), bevacizumab (Bev), and cyclophosphamide (Cy) elicited neoantigen-specific T cells and prolonged OC survival. Here, we hypothesize that adding acetylsalicylic acid (ASA) and low-dose interleukin (IL)-2 would increase the vaccine efficacy in a recurrent advanced OC phase I trial (NCT01132014). By adding ASA and low-dose IL-2 to the OCDC-Bev-Cy combinatorial regimen, we elicited vaccine-specific T-cell responses that positively correlated with patients' prolonged time-to-progression and overall survival. In the ID8 ovarian model, animals receiving the same regimen showed prolonged survival, increased tumor-infiltrating perforin-producing T cells, increased neoantigen-specific CD8 <sup>+</sup> T cells, and reduced endothelial Fas ligand expression and tumor-infiltrating T-regulatory cells. This combinatorial strategy was efficacious and also highlighted the predictive value of the ID8 model for future ovarian trial development