Periodic Reporting for period 3 - ASTEROID (ASTronomy EuROpean Infrared Detection) Reporting period: 2019-07-01 to 2021-11-30 Summary of the context and overall objectives of the project Classical IR detectors used for tactical or space missions are mainly linear arrays or two dimensions Focal Plane Arrays (FPA) which designs are compatible with the scene to observe. For defense applications, the typical scenes to observe include vehicles, humans and buildings. For Earth observation missions from satellites, the scenes to observe are landscapes, ground, sea and atmosphere. These applications require detectors compatible with IR flux from Near IR (NIR), ShortWave IR (SWIR), MidWave IR (MWIR) and LongWave IR (LWIR). The fluxes coming from these scenes are in the range of 1000 to 1e6 photons/seconds/pixel. Moreover, the sizes of the classical detector used for these applications are XGA format at maximum (range 1000x1000 pixels).However, for science and astronomy, specific infrared (IR) detectors are required. These types of detectors have their own specificities. These focal plane arrays (FPA) need to be very large (> four million pixels) and compatible with very high performances. Today large dimension infrared focal plane arrays (IR FPA) are only available from US Company Teledyne. Its Hawaii-2RG FPA (2048x2048 pixels, 18 µm pitch) is installed on all major ground based observatories. Europe is thus until today dependent on US for large format arrays in NIR and SWIR. To be able to manufacture very large FPA, 4 key constraints exist. Indeed large FPA require: - Very large dimension Read Out Integrated Circuits (ROIC)- Very large substrates (mono-crystalline CdZnTe alloy);- The capacity to epitaxy high quality HgCdTe material on these substrates;- A manufacturing line fully compatible with large substrate dimensions.Thus the whole industrial chain must be adapted especially if the number of detectors to produce is important.The main objective of the ASTEROID project is thus to extend the dimension of high performance infrared FPA that can be manufactured in Europe to dimensions equivalent to that of the HAWAII FPA, overturning all constraints mentioned above. This will allow Europe to become independent for the procurement of this type of detectors. The targeted format is 2k² 15µm pitch FPA (2048x2048 pixels).It has here to be noted that synergies with ALFA ESA program and ASTEROID exists. ESA has launched for years development of Astronomy IR detector. Today, ALFA (Astronomy Large Focal Array) is dealing with the development of 2048x2048 15µm pitch IR detector. This program runs with CEA-LETI and CEA-IRFU in France and is funded by ESA and Labex FOCUS. At the end of the project the Consortium results are really enthousiastic. The technologies developped demonstrates that both industrial capability demonstration for large detector manufacturing is accessible. In terms of performances, the prototypes developped reached utmost performances comparable to state of the art.Thanks to CEA-LETI and Lynred efforts, large MCT materials and Silicum wafers are available at Lynred and will be used for futur programs were very large infrared detectors are requested. EVG has developped tools methods and process that can be usefull for that purpose. On modeling parts, ADDL computed a thermo-mechanical simulator for infrared detectors, validated with internal measurements on real detectors at Lynred. CEA-IRFU tested very low dark current comparable to state of the art, with TV format detectors p/n SWIR, achieved in the frame of that program. IFAE laboratory increase its testing and charaterization skills in the infrared domain and demonstrates that the 2K² structure is really reliable after numbers of thermal cylcling at cold temperature. Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far period 05/2017-05/2018 :• WP1 : Evaluation of new method for Silicon wafers processing compatible with large 8’’ ROIC wafers• WP2 : Preparation, design and validation of all the tooling necessary to manufacture the objects during the second period of the program (06/2018-05/2019). • WP3 : Preparation of the test plan for the test vehicle • WP3 : Specification of the modeling tool • WP3 : Simulation of the impact of the CdZnTe substrate thinningA public brochure and a website have been issued during this period also.period 1/05/2018-30/06/2019:Important results have been obtained regarding all the different technologies involved in the program. • ASTEROID will use as expected ALFA ROIC, indeed the probe test at 300K are OK.• Innovated processes developed at EVG are under interest for Lynred manufacturing line for both bonding and photolithography process and equipments• CEA-LETI and Lynred have demonstrated the feasibility to manufacture very large CdZnTe ingots, HgCdTe LPE and PV processes with quality and critical parameters comparable to internal standards• Lynred has obtained the very first ALFA 2048x2048 hybridized circuit and analyzes that the connectivity of the diode is very promising • ADDL is developing a full model of the 2048x2048 15µm pitch able to simulate this very large detector• IFAE and CEA-IRFU have started to prepare their tests facilities and equipments to be ready to test TVand 2K² test vehicles.period 1/06/2019-30/11/2021 + the detection circuit p/n SWIR TV format were manufacrured at Lynred and detectors were hybridized+ the TV format prototypes were sorted at CEA-LETI and then send to CEA-IRFU for full characterization+ the 2K² prototypes were manufactured and assembled into packaging for delivery to IFAE laboratory+ The 2K² detecors were integrated into dedicated test bench for thermal cycling at IFAE and operability and behaviours were analyased Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far) At the end of the project we want to demonstrate that the manufacturing of very large MCT wafer is possible and that it can be used in an industrial way. In detail, we want to achieve the main objectives:- WP1 : ROIC 8’’ process compatible with Sofradir standards showing equivalent results as the current industrial line- WP2 : MCT wafer (at LETI and/or Sofradir) showing good characteristics (mechanical, material quality, cosmetics) and also electro-optical results equivalent to the one obtained on the previous n/p TV format detector for ESA with low dark current and high quantum efficiency- WP3 : hybridized circuit 2K² will be manufactured. We want to assess the reliability of the hybridized process showing that even after thermal cycling, the operability is still correctThe impacts of such results are described hereafter:• Reduce the dependence on critical technologies and capabilities from outside Europe for future space applications,• Develop, or regain in the mid-term, the European capacity to operate independently in space, e.g. by developing in a timely manner reliable and affordable space technologies• Enhance the technical capabilities and overall competitiveness of European space industry satellite vendors on the worldwide market. • Open new competition opportunities for European manufacturers by reducing the dependency on export restricted technologies that are of strategic importance to future European space efforts.• Enable the European industry to get non-restricted access to high performance technologies that will allow increasing its competitiveness and expertise in the space domain. • Improve the overall European space technology landscape and complement the activities of European and national space programs. 20180808-publishable-summary-image.jpg
