MerlinEM
The MerlinEM Direct Electron Detector (DED) is an advanced detector development in the field of Electron Microscopy, combining direct detection of electrons and rapid readout in a pixelated format ideal for applications such as 4D STEM and TEM dynamic imaging. Each sensor pixel is individually bump-bonded to an intelligent chip which uses threshold discriminators to distinguish electrons from the background, effectively eliminating all readout noise. This allows for integral mode imaging where multiple short exposure images are acquired and summed together. Uniquely, neighbouring pixels can communicate to mitigate charge-sharing effects, and this, combined with the direct detection of electrons, yields enhanced performance. As beam energies decrease toward 60 keV, the Merlin for EM has been shown to provide near-ideal DQE and MTF detector response.


MerlinEM Installation Sites
Title | Address | Description |
---|---|---|
University of Glasgow | Glasgow G12 8QQ, UK | |
University of Oxford | Diamond House, Harwell Science and Innovation Campus, Fermi Ave, Didcot OX11 0DE, UK | |
NIST | 100 Bureau Dr, Gaithersburg, MD 20899, USA | |
University of Victoria | Victoria, BC V8P 5C2, Canada | Detector Installed – Visit the group website |
EMAT University of Antwerp | Prinsstraat 13, 2000 Antwerpen, Belgium | Detector Installed – Visit the group website |
MPI Stuttgart | Heisenbergstraße 3, 70569 Stuttgart, Germany | Detector Installed – Visit the group website |
Ernst Ruska Centre | 52428 Jülich, Germany | Detector Installed – Visit the group website |
Brookhaven National Laboratory | 98 Rochester St, Upton, NY 11973, USA | Detector Installed – Visit the group website |
RIKEN | Japan, 〒351-0105 Saitama, Wako, Nishiyamatodanchi, 2−1 2-1 | Detector Installed – Visit the group website |
The Univeristy of Queensland | St Lucia QLD 4072, Australia | Detector Installed – Visit the group website
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TU Darmstadt | Karolinenpl. 5, 64289 Darmstadt, Germany | Detector Installed – Visit the group website |
University Paris Sud | 15 Rue Georges Clemenceau, 91400 Orsay, France | Detector Installed – Visit the group website |
National University of Singapore | 21 Lower Kent Ridge Rd, Singapore 119077 | Detector Installed – Visit the group website |
Fraunhofer Institute for Microstructure of Materials and Systems IMWS | Walter-Hülse-Straße 1, 06120 Halle (Saale), Germany | Detector Installed – Visit the group website |
Wuhan University | Wuchang District, Wuhan, Hubei, China, 430072 | Detector Install upcoming – Visit the group website |
TU Berlin | Straße des 17. Juni 135, 10623 Berlin, Germany | Detector Installed – Visit the group website |
Shanghai Tech University | 393 Huaxia Middle Rd, Pudong Xinqu, China, 201210 | Detector Install upcoming – Visit the group website |
Norwegian University of Science and Technology (NTNU) | Høgskoleringen 1, 7491 Trondheim, Norway | Detector Installed – Visit the group website |
The University of Cambridge | The Old Schools, Trinity Ln, Cambridge CB2 1TN, UK | Detector Install upcoming – Visit the group website |
University of Texas in Austin | Austin, TX 78712, USA | Detector Install upcoming – Visit the group website |
University of Manchester | Oxford Rd, Manchester M13 9PL, UK | Detector Installed – Visit the group website |
CNRS - Institut Néel | 25 Avenue des Martyrs, 38042 Grenoble, France | Detector Installed – Visit the group website |
University of York | Heslington, York YO10 5DD, UK | Detector Install upcoming – Visit the group website |
University Paris Sud- Orsay | 15 Rue Georges Clemenceau, 91400 Orsay, France | Detector Install upcoming – Visit the group website |
MPI Stuttgart | Heisenbergstraße 1, 70569 Stuttgart, Germany | Detector Install Upcoming – Visit the group website |
Shenzhen Read Crystal Technology | 447 Huangge Rd, Long Gang Zhong Xin Cheng, Longgang Qu, Shenzhen Shi, Guangdong Sheng, China | Detector Install Upcoming – Visit the group website |
Erich Schmid Institute of Materials Science | Akademie der Wissenschaften, Jahnstraße 12, 8700 Leoben, Austria | Detector Install Upcoming – Visit the group website |
EPFL | Route Cantonale, 1015 Lausanne, Switzerland | Detector Install Upcoming – Visit the group website |
Lille University | 42 Rue Paul Duez, 59000 Lille, France | Detector Install Upcoming – Visit the group website |
Xi'An Jiaotong University | 28 Xianning W Rd, Jiao Da Shang Ye Jie Qu, Beilin Qu, Xian Shi, Shaanxi Sheng, China, 710050 | Detector Install Upcoming – Visit the group website |
Guangdong Jihua Lab | Guicheng Subdistrict, Foshan, Nanhai District, Foshan, Guangdong Province, China | Detector Install Upcoming – Visit the group website |
Inst of Metal Research, CAS (IMRCAS) | 72-19 Wenhua Rd, Shenhe Qu, Shenyang Shi, Liaoning Sheng, China, 110005 | Detector Install Upcoming – Visit the group website |
Applications
4D STEM
Diffraction imaging
Low Dose Imaging
Electron Energy Loss Spectroscopy
Ptychography
TEM imaging
Our MerlinEELS Application Note shows how users have applied High kV core-loss imaging to their EELS application where electron counting and zero-read out noise are crucial. Additionally the high dynamic range of the detector is demonstrated in zero-loss peak area.
The MerlinEM 4D STEM Application Note outlines MerlinEM’s use in imaging of electro-magnetic fields in nano beam diffraction and in atomically resolved imaging.
In this note, we will show examples of using a MerlinEM detector to generate established signals in STEM. We will use LiberTEM2software to reconstruct the data and specifically its GUI web interface. We will show examples of virtual STEM images and convergent beam electron diffraction (CBED) from a few different samples
Our MerlinEM Ptychography Application Note explores the reconstruction of samples complex phase with two different modes of ptychography in 4D-STEM
Specifications
Rapid Gapless Readout and high dynamic range
Kilohertz frame rates in continuous mode with zero deadtime offers more experimental flexibility than ever before, minimising effects such as sample drift, and enabling single shot and “pump and probe” dynamic experiments. Up to 24-bit counting depth enabling 1:16.7 million intensity range in a single image, ideal for recording diffraction patterns.
Region of Interest
MerlinEM offers an exciting opportunity to image a subset of the Medipix3 chip and achieve faster frame speeds. The ROI Rows allows the user to select how many Rows the software will read from the detector. The following schematic demonstrates the possible speed advantages when using ROI. This mode can be used to significantly speed up the STEM acquisition.
Effectively noise free
Two threshold discriminators in each pixel means zero read noise and dark current. (a) Pixel event schematic. (b) Principle of electron counting, signal is only collected when deposited in the pixel is above threshold. (c) Schematic of the pixel logic.
Adapted from Paterson GW et al, Ultramicroscopy, 2020, Vol 210 under CC 4.0 licence
Charge Summing Mode (CSM)
“Charge Summing Mode” (CSM) is a useful mode which can be applied to the lower energies of the TEM range (60-120 kV, potentially even higher). It was designed to allow for a better detection of particles striking close to the pixels’ edge and to alter charge spreading. For example, if the threshold is set to 70% of the beam energy, an electron striking the edge of the pixel may not be counted in a standard, single pixel mode. It will not deposit enough energy to trigger the count in any pixel. If CSM mode is active, the detector electronics will compare the charge in the neighbouring pixels and assign it to the pixel with the largest deposited charge. The sum of the deposited energies will be compared against the threshold. This maximises the DQE response of the detector.
Software
MerlinEM MIB data is in an open format. The various acquisition modes, as well as many other input parameters for the optimisation of the MERLIN system, are easily chosen by a user friendly Graphical Interface as well as remotely controlled via TCP/IP protocol, and Digital Micrograph. The MerlinEM software now includes an exciting opportunity to visualise 4D-STEM datasets in real time. Annular, bright field and DPC virtual detection is available in our new STEM interface.
Publications
Recently published articles including MerlinEM data:
- Detectors—The ongoing revolution in scanning transmission electron microscopy and why this important to material characterization
APL Materials 8, 110901 (2020); Ian MacLaren, Thomas A. Macgregor, Christopher S. Allen, and Angus I.Kirkland
https://doi.org/10.1063/5.0026992https://aip.scitation.org/doi/full/10.1063/5.0026992
- Spontaneous creation and annihilation dynamics and strain-limited stability of magnetic skyrmions
Nature Communications volume 11, Article number: 3536 (2020) Frederic Rendell-Bhatti, Raymond J. Lamb, Johannes W. van Der Jagt, Gary W. Paterson, Henk J. M. Swagten & Damien McGrouther
https://www.nature.com/articles/s41467-020-17338-7
- Local Crystallinity in Twisted Cellulose Nanofibers
ACS Nano (2021) Tom Willhammar*, Kazuho Daicho, Duncan N. Johnstone, Kayoko Kobayashi, Yingxin Liu, Paul A. Midgley, Lennart Bergstrom, and Tsuguyuki Saito
https://pubs.acs.org/doi/10.1021/acsnano.0c08295
- Performance-limiting nanoscale trap clusters at grain junctions in halide perovskites.
Nature 580, 360–366 (2020). Doherty, T.A.S., Winchester, A.J., Macpherson, S. et al. https://doi.org/10.1038/s41586-020-2184-1
- Direct Imaging of Correlated Defect Nanodomains in a Metal–Organic Framework.
Collins: Journal of the American Chemical Society 2020 142 (30), 13081-13089 Duncan N. Johnstone, Francesca C. N. Firth, Clare P. Grey, Paul A. Midgley, Matthew J. Cliffe, and Sean M.
DOI: 10.1021/jacs.0c04468
- High-speed direct detectors such as MerlinEM are discussed in the forthcoming Handbook on Big Data and Machine Learning in the Physical Sciences
Volume 2: Advanced Analysis Solutions for Leading Experimental Techniques, Chapter 5: Next-Generation Information Technology Systems for Fast Detectors in Electron Microscopy. This work is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License. Dieter Weber , Alexander Clausen and Rafal E. Dunin-Borkowski
https://doi.org/10.1142/9789811204579_0005