SILICON SENSOR ACTIVITIES AT SINTEF MINALAB. Marco Povoli, Angela Kok, Ozhan Koybasi

Transcription

1 SILICON SENSOR ACTIVITIES AT SINTEF MINALAB Marco Povoli, Angela Kok, Ozhan Koybasi

2 Outline 1. SINTEF MiNaLab 2. Silicon radiation detector history Pad, strip, pixel and silicon drift detectors 3. Overview of current R&D activities 4. A few example of latest results 2

3 SINTEF MINALAB (Micro- and Nanotechnology Laboratory, Oslo) The most advanced laboratory in Norway for micro- and nanotechnology, situated on the campus of University of Oslo Clean room facilities of 800 m 2 General cleanroom area of class 1000 and mini environments of class 10 for sensitive processes Complete Si processing line for 150 mm (6 in) wafers with state-of-the-art production equipment Another line for Non-CMOS compatible materials Throughput of 10,000 wafers per year 3 ISO (Quality Management system) and ISO (Environmental Management system) certified

4 EQUIPMENT and KEY PROCESSESOslo) High temperature processes in furnaces at C (thermal oxidation, gas phase doping, annealing, LPCVD of SiN and polysilicon) Deposit various thin layers on the surface (sputter, PECVD, PLD, ) Etch thin layers (RIE, wet etch) Making patterns on the wafers (automated photolithography line, NIL) Etch 3-dimensional structures in the silicon wafer (state of the art DRIE, anisotropic wet etch) Various characterization equipment (4-point probe, automatic inspection, probe stations, ellipsometer, interferometer, profilometer, SEM) Bond wafers to form a stack (anodic, fusion, metal, adhesive) Packaging (wafer dicing, wirebonding) 4

5 SINTEF MINALAB From idea to manufacturingoslo) Research and development > 40 industry partners every year (1/3 international companies) Commercialisation (Small scale production/ pre-series production) Production of components for both national and international customers based on either - Proprietary technologies (patented) Funding sources - Custom designs Support of high-volume product development Technology developed at MiNaLab has been central in several successful start-ups (PreSens, polight, GasSecure, ) Operating revenue of ~8.5 million USD in

6 RESEARCH, DEVELOPMENT and PRODUCTION ACTIVITIES MEMS Micro Optics Pressure sensors Inertial sensors Energy harvesting Ultrasound transducers Gas detection (single and multi-gas technologies) Micro optical device (micro camera, micro mirror) Displacement sensors/accelerometers with optical readout Medical Sensors and BioMEMS Lab-on-a-Chip In vivo sensors and biocompatibility Microfluidics Biosensors Radiation detectors Silicon pad, micro-strip and pixel sensors Silicon Drift Diodes (SDD) 3D and active edge silicon sensors Sensors based on other materials: SiC, diamond, graphene, Detection of photons from IR to γ-ray range, charged subatomic particles, neutrons 6

7 Outline 1. SINTEF MiNaLab 2. Silicon radiation detector history Pad, strip, pixel and silicon drift detectors 3. Overview of current R&D activities 4. A few example of latest results 7

8 SILICON RADIATION SENSORS A leading supplier of silicon radiation sensors for scientific and industrial applications for nearly 30 years Pad, pixel, single-sided, double-sided strip sensors One of few suppliers worldwide of low noise Silicon Drift Diodes P-on-N, N-on-N, N-on-P configurations 10 µm to 2 mm detector thickness SINTEF's process leads to sensors with excellent electrical characteristics: -extremely low leakage current (<100 pa/cm 2 ) -very high breakdown voltages( >1000 V) Thin Thick 8

9 APPLICATIONS High energy physics (CERN, Fermilab, Brookhaven, ) X-ray spectroscopy Synchrotron imaging applications (DESY, SLAC) Space telescopes Radiation monitoring in space Mammography Waste management Dental X-ray and CT scanning Defence / Homeland security Medical dosimetry 9

10 Outline 1. SINTEF MiNaLab 2. Silicon radiation detector history Pad, strip, pixel and silicon drift detectors 3. Overview of current R&D activities 4. A few example of latest results 10

11 Overview of current R&D activities Two key approaches Utilisation of Micromachining Technology Few technology are close to full production level New Materials Graphene Silicon carbide Conceptual level Pyramids Aspect ratio ~1:30 11

12 MICRO-MACHINING 3 dimensional (3D) electrodes -Ultra-high radiation hardness Edgeless capability - Minimal dead area - Large area seamless imaging - Edge-on operation Active edge (doped trench) Active edge pixel sensor Pixel sensor with guard rings 12

13 MICRO-MACHINING Increased surface area - Improved neutron detection efficiency Well-defined microscopic volumes Removal of excess Si and replacement with tissueequivalent materials Neutron converter ( 6 LiF) is deposited on backside with inverted pyramids or V-grooves N- silicon N+ silicon P+ silicon Aluminum Oxide Pyramids 13

14 Through silicon vias (TSV) stacking Stacking of 3 silicon strip sensors via TSVs TSVs are made by etching deep trenches through sensor substrate by DRIE and filling them with highly doped polysilicon TOP sensor MIDDLE sensor 14 BOTTOM sensor

15 Graphane-based photodetectors and radiation detectors Graphene is a single layer of C-atoms arranged in hexagonal honeycomb lattice Exceptional electronic properties such as ultrahigh mobility (>100,000 cm2/vs) have led to many device applications including photodetectors and radiation detectors Ongoing research project (GraSeRaD) funded by the Research Council of Norway (~1.2 million USD) to investigate graphene based radiation detectors and photodetectors 15

16 Double type full columns Full p-type, partial n-type columns 3D SILICON DETECTORS FOR HIGH ENERGY PHYSICS Ongoing R&D on 3D sensors at SINTEF mainly for the upgrade of ITK detector at CERN Wafer layout includes 3D sensors compatible with various readout chips: FE-I4, FE-I3, FE-I65, RD53, CMS, Medipix A new fabrication run has just been completed completed sucessfully SOI and Si-Si wafers 100 µm and 50 µm sensor thicknesses Active edge ~4 µm DRIE holes SOI wafers Si-Si wafers 16 Upcoming prototyping runs for SINTEF to be a production site before 2019

17 3D SILICON DETECTORS FOR HIGH ENERGY PHYSICS ATLAS p+ columns CMS 3D diodes n+ columns Active edge V dep < 5V Yield of 90%! Before sintering After sintering 17 Before sintering Before sintering

18 3D detectors for micro dosimetry Microdosimetry: Study of the distribution of the energy deposited in well-defined microscopic volumes Aims at relating the type and amount of radaition to a biological effect Required due to the stochastic nature of radiation interaction with small volumes Gold standard: "Tissue Equivalent Proportional Counter" Size limitation (bulky) Requires rather large operating voltages Solid-state microdosimetry can help overcome TEPC limitations 18

19 3D Microdosimeter Al flourescence Tests at ID21 X-ray microscope at the ESRF after electrical screening 19

20 3D detectors for micro dosimetry 20 Idea based on a patent from the Center for Medical Radiation Physics (Univeristy of Wollongon, Australia) Remove excess silicon outside the cells Back-fill with tissue-equivalent polymer (e.g. Polyimide) Mimic interaction of radiation with human cells Detect both primary and secondary charged particles produced in the radiation field Possible to detect recoils produced by fast neutrons interaction with polyimide

21 Development of Neutron Image Sensor Technology Developing a prototype of position sensitive silicon radiation detector for neutrons: With a high neutron sensitivity and excellent position resolution With a low sensitivity to X- and gamma-ray photons Small with a low power consumption Applying relatively low cost technology, not reliant on 3 He Multiple silicon strip detectors are stacked together with neutron converter material ( 6 LiF) in between Backside of silicon strip detectors configured into pyramids or V-grooves for higher neutron detection efficiency Stack of silicon strip detectors 21

22 Development of Neutron Image Sensor Technology No LiF Thin layer of LiF 6 Li + n a (2.05 MeV) + 3 H (2.72 MeV) a - ~ 6 mm 3 H - ~ 32 mm Thick layer of LiF 22

23 Summary Long standing track record in silicon radiation detector Leader in 3D based radiation detectors Many exciting developments in the past years Ready for commercialisation and many application areas Open for all possible applications and collaborations 23

24 Technology for a better society