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energy (nm) Applications Wide bandgap material CONFIDENTIAL Other Spectroscopy Tools Attolight CL • expensive (far UV) • low spatial resolution • difficult to use • not versatile 260 230 Boron Nitride 200 0 200 400 time (ps) © 2013 Attolight AG. All Rights Reserved. 24
attolight Attolight AG EPFL Innovation Square PSE D 1015 Description Lausanne Switzerland t The +41 core 21 626 piece 0100 of Attolight's instrument is a custom designed scanning electron microscope www.attolight.com (SEM). SEM is a widely used scanning probe technology since it has the ability to image the surface features of a sample with very high spatial resolutions going below one nanometer (10 -9 m) today. An SEM consists of an electron source and electron optics that focuses the electron beam to a nanometer sized spot. The image (or map) is constructed by scanning the electron beam over the sample point by point (see Fig. 1). The impinging electron beam on the sample surface creates secondary electrons and photons that are emitted. At each scanned point on the sample, the intensity of the secondary electron (SE) signal is recorded and a pixel is shown on the screen with a grey scale level proportional to the SE signal intensity. incoming electron beam TECHNOLOGY BRIEF Attolight uses a proprietary technology to create ultrashort electron pulses instead of a continuous electron beam (see Fig. 2). The SEM and electron source have to be custom designed to reach high spatial resolutions and short pulses. Our new tool will deliver a few nanometers spatial resolution and pulses shorter than 10 picoseconds (1 picosecond = 10 -12 s) at a repetition rate of typical 80 MHz (repetition rate can be changed easily). The photoelectric effect is used to create such short electron pulses: short UV laser pulses are sent on a thin metal film which creates short electron pulses. The design and manufacturing of the electron source is a core competence of Attolight. A lot of care has to be taken in designing the electron source and the electron optics in order to keep the pulses short and well focused and still intense enough to carry out measurements. electrons incoming electron beam Sample light Fig. 2 Attolight technology electrons Sample light Fig. 1 Principle of standard SEM Time resolved spectroscopy This is our “home” application in the R&D market. Initially, the tool was built for this application. We exploit a phenomena called cathodoluminescence (CL): some semiconductors emit light when they are bombarded with an electron beam containing electrons carrying a certain energy. This light is called CL and contains a lot of information on optical properties of the material under test. CL is often used to analyse semiconductor based nanostructures since the spatial resolution is very high. CL is a excitation spectroscopy technique with very high spatial resolution. Our idea was not just to look at a continuous CL signal but also at the lifetime of the signal in the picosecond regime. To achieve this we adapted an ultrafast light detector (STREAK camera) to our instrument. We call this tool pTRCL (picosecond time-resolved CL). © 2011 Attolight AG - All rights reserved.
Page 1 and 2: CONFIDENTIAL © 2011 Attolight AG.
Page 3 and 4: Who are we CONFIDENTIAL Swiss Compa
Page 5 and 6: Introduction CONFIDENTIAL Text •
Page 7 and 8: Attolight CL System Integrated Cath
Page 9 and 10: Attolight CL System Embedded Optica
Page 11 and 12: Attolight CL System Time-Resolved C
Page 13 and 14: Applications Gallium Arsenide singl
Page 15 and 16: Applications Sulfur diffusion in Cd
Page 17 and 18: Applications Strain analysis in Zin
Page 19 and 20: Applications / Production Qualifica
Page 21 and 22: Applications Local Lifetime Measure
Page 23: Applications CONFIDENTIAL Local Lif
Page 27 and 28: attolight dinates of the excitation
Page 29 and 30: Applications - LED performance and
Page 31 and 32: Be Part of the New Cathodoluminesce

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