Engineering Tripos Part IIB

Projects (2011-12)  (under development)

A range of projects, several computer-based, are being offered in the areas of:-

Note: there is no expectation that you will have prior experience of electron microscopy before undertaking any of these projects - any training or familiarisation necessary will be part of the project; from our experience of past projects, we find that most people regard this as a highly interesting and illuminating part of the work.

 

Further Details

MicroMap - a Google Earth approach to scanning electron microscopy

  

REFERENCE 2009-B-DMH-1
TITLE MicroMap - a Google Earth approach to scanning electron microscopy 
SUPERVISOR Dr D M Holburn and Dr Nicholas Caldwell
EMAIL Contact Information 

"Google Earth", "Google Maps", and similar software provide an elegant and effective way for users to explore the world, identify landmarks and find routes from one location to another. Google has applied this idea on the macro-scale and the astronomical scales; we would like to apply this idea to the microscopic and nano-scale world that can be seen using scanning electron microscopes (SEMs). 

Scanning electron microscopes can be used to observe and measure features on many different kinds of samples. Biological samples are frequently uncoated and fragile, yet must be viewed by a high energy electron beam in a hostile high vacuum environment. Despite recent advances in technologies which minimise beam damage to samples, operators still have a limited time-frame to obtain usable results before specimen charging and/or beam damage become excessive. 

The "Google Earth" concept provides a means of reducing the inevitable damage and extending the microscope operator's window of opportunity. To turn concept into reality, the strategy will involve mapping the surface of the sample, capturing and storing images to create a high-resolution image database. The microscope user will then be able to revisit previously scanned areas of the sample surface without further exposing it to the electron beam. Novel image manipulation and management techniques will need to be developed for this purpose. The software will also need to interface with the existing SEM API in order to automatically control components of the SEM including the electron gun, stage and focusing. 

This project addresses a real need identified by microscope users and manufacturers, and will be run in collaboration with Carl Zeiss, one of the leading manufacturers of Scanning Electron Microscopes (SEM) worldwide, and a research partner of CAPE (the Centre for Advanced Photonics and Electronics in the Department of Engineering). 

This is a software engineering project which will best suit someone with experience and / or interest in developing programming skills using C++, Java, Visual Basic or Matlab/Octave. An interest in image processing will also be advantageous.

For more details - see Contact Information.


Image Processing in a Multiprocessor World

REFERENCE 2009-B-DMH-8
TITLE Image processing in a Multiprocessor World 
SUPERVISOR Dr D M Holburn and Dr Nicholas Caldwell 
EMAIL Contact Information 

Today's high-end desktops and laptops are no longer single processor machines. Dual-core processors are commonplace even for entry-level systems, quad and multi-core processors are already available. The recent emergence of the nVidia multi-processor graphics accelerator and CUDA software development environment provides another avenue for performance enhancement in compute-intensive image processing applications.  Many applications, however, are simply not designed to exploit such  parallel processing capabilities, leaving much of the computer's potential untapped and idle. It is likely that redesigning existing applications to harness multiprocessors will be an integral part of many commercial software projects in the short and medium-term future - making this project an ideal introduction to the field. 

The challenge of this project is to explore the potential of these developments, through the implementation of a benchmark program for panoramic photo stitching, and to identify areas in the science of scanning electron microscopy in which these approaches can help make the operation of the instrument and the interpretation of its image easier and more convenient than ever before. Scanning electron microscopes are widely used in many diverse fields of science and industry. 

This project will be run in collaboration with Carl Zeiss SMT, one of the leading manufacturers of scanning electron microscopes worldwide, and a research partner of the Centre for Advanced Photonics and Electronics (CAPE) at the Department of Engineering. Carl Zeiss will provide an introduction to SEM technology as well as sample images for development and testing purposes and assistance with interfacing to their microscope control software. 

This project calls for some programming experience (most likely in C++ for the PC, though Java and/or Matlab/Octave experience would also be acceptable) and an interest in digital image processing - any experience in this area through appropriate modules from group F will be highly beneficial.

The nVidia GPU - Parallel Processing with CUDA

http://www.nvidia.co.uk/docs/IO/55972/220401_Reprint.pdf

A local course on CUDA Course is being organised in Cambridge from 25-27 May 2009. Details are here:

http://www.many-core.group.cam.ac.uk/course

Admission is free, but pre-registration is required.  Unfortunately, Part IIA projects are likely to clash with this, but it is possible a repeat might be offered in future, 

For more details - see Contact Information.


Supporting Fault Diagnosis in Scanning Electron Microscopes

evo50

REFERENCE 2009-B-DMH-3
TITLE Supporting Fault Diagnosis in Scanning Electron Microscopes 
SUPERVISOR Dr D M Holburn and Dr Nicholas Caldwell
EMAIL Contact Information 

Carl Zeiss SMT, one of the leading manufacturers of scanning electron microscopes worldwide, has recently entered into partnership with the Centre for Advanced Photonics and Electronics (CAPE) at the Department of Engineering.

Effective fault diagnosis is a critical value-added service component for scientific instrument manufacturers. A reputation for efficient service support can be the tipping point that wins or loses a contract, but providing that support can be expensive to the manufacturer. We have previously developed web-based expert systems using artificial intelligence (AI) techniques that can help service engineers diagnose faults in scanning electron microscopes (SEMs) remotely, and have explored fault database approaches using web-based front ends for both diagnosis and database maintenance.  Our FirstAID development is a combination of html and php interacting with a Microsoft Access database. 

This project will focus on improving the usability of our FirstAID system and enabling it to harness third-party testing software to remotely probe SEM hardware. Emerging and future SEMs will allow even more of their internal hardware to be probed remotely by secure routes through corporate firewalls, so this approach is expected to be a profitable one. The intended goal is that FirstAID will be able to support both the "final test" phase of SEM manufacturing and operational fault diagnosis by service engineers and suitably trained microscope users. 

This project will be run collaboratively with Carl Zeiss SMT, who will provide an introduction to SEM technology and access to service engineers. It will call for some programming experience and an interest in web technologies.

For more details - see Contact Information.


SEM Image Searcher - searching microscopy image collections

evo50

REFERENCE 2009-B-DMH-4
TITLE SEM Image Searcher - searching microscopy image collections
SUPERVISOR Dr D M Holburn and Dr Nicholas Caldwell 
EMAIL Contact Information 

Today's computerised scanning electron microscopes (SEMs) make it both easy and virtually cost-free to save the images appearing on the SEM's monitor as high-quality digital micrographs. For many SEM applications, those high-resolution images contain critical information needed by scientists, engineers and other experts. Since storage space is relatively cheap, microscopists may save dozens, even hundreds, of digital images from a single sample.

Creating images is easy; finding a particular relevant image again may not be. Using sensibly named directories and image filenames helps, but there are limits to how much information can be compressed into a filename and even the best cataloguing by directory structure means that there is only one route to and one organizational configuration for the images. Even Google and its image search application would struggle with just the filenames to work with.

SEM images can be saved in formats such as TIFF where additional textual information can be stored with the image. Such information can include instrument settings used when the image was captured, the size, number and type of features, etc. By using this information, it would be possible to classify, index, and search image collections by associated image content.

This project would focus on creating software to index and search image collections using TIFF associated information, and would consider what information should be stored by TIFF and/or via transparent XML associated files, possibly proposing a standard for this area. If time permitted, an extension would seek to use simple image analysis techniques to supplement textual searching.

This project will be run collaboratively with Carl Zeiss SMT, a leading manufacturer of scanning electron microscopes worldwide, who are partners with the Centre for Advanced Photonics and Electronics (CAPE) at the Department of Engineering. Carl Zeiss SMT would provide access to and assistance with their TIFF encoding strategies, and supply image collections for testing. This project will call for some programming experience and a willingness to learn more about search techniques.

For more details - see Contact Information.


Drawing Vectorisation for Focused Ion Beam Milling

REFERENCE 2009-B-DMH-5
TITLE Drawing Vectorisation for Focused Ion Beam Milling
SUPERVISOR Dr D M Holburn and Dr Nicholas Caldwell 
EMAIL Contact Information 

The focused ion beam (FIB) instrument is a tool used in the semiconductor industry and materials science fields for analysis, deposition and ablation of material at specific sites on a suitable sample. FIBs can be used for micro-machining and nano-machining, and a typical example of their use is to patch or modify an existing semiconductor chip.

FIBs are fully computer-controlled instruments, able to control the movement of their ion beam and their specimen stage with an extremely high degree of accuracy, precision and reproducibility. Thus FIBs can be used to etch arbitrarily complex patterns onto sample surfaces.

However the format in which those patterns are presented can adversely impact both the efficiency and effectiveness of the etching process. Whenever the ion beam is switched on, it will etch the sample and the etching process will cause sputtering to occur on the exposed sample surface. The longer the ion beam remains on a particular site (or more frequently it revisits a site), the deeper the etch created. Thus bit-mapped (raster) drawings (BMPs, GIFs, JPGs) are particularly unhelpful for ion-beam milling. Vector-based drawings (e.g. SVG) are much more useful. However, being vector-based is not sufficient for optimal milling. It is necessary to determine the optimal sequencing of vectors, taking into account the "third" dimension of etch depth / dwell time.

This project will first look at methods to "vectorise" existing raster-based drawings and current vector graphics standards. The next stage will then be to design and implement algorithms to optimally sequence the vectors into an ion beam milling points list (set of x- and y-coordinates with dwell time), and to evaluate the complete package on a real FIB instrument.

This project will be run collaboratively with Carl Zeiss SMT, a leading manufacturer of FIB instruments worldwide, who are partners with the Centre for Advanced Photonics and Electronics (CAPE) at the Department of Engineering. Carl Zeiss SMT will provide an introduction to FIB technology and assistance with FIB-related software packages. This project will call for some programming experience and a willingness to learn about related algorithms.


Computer-Aided Design of Mixed-Signal CMOS IC

REFERENCE 2008-B-DMH-6
SUPERVISOR Dr D M Holburn
EMAIL Contact Information 

This computer-based design project provides opportunities to gain familiarity with the latest version of the professional Mentor Graphics CAD tools for IC design recently made available on the Department Teaching System. These tools are widely used in industry and by research laboratories. 

The proposed design is a high performance integrated 'System on a Chip'. It will be a mixed-signal system, spanning analogue and digital technologies, and it's intended the design will form the basis of next year's Part IIA project on VLSI Design. Alternatively, within broad limits there will be opportunities within this specification for individuals to develop designs of their own choosing, perhaps based on suggestions from a sponsor.  

This project may be particularly attractive to those who have aspirations towards a career or research in IC design.

There is  a Powerpoint presentation on the web (intended for training purposes) which gives a flavour of the features of the new Mentor ICStudio Environment.  NB this is a large download (16 Megabytes), and is only available from a workstation within the University intranet (on  .cam.ac.uk)

In addition, a local company which is at the forefront of Gigahertz CMOS RF integrated circuit technology is interested to sponsor a number of projects being undertaken by keen and ambitious designers.  Considerable support will be available for eligible designs.  

Here are a few ideas for project designs, some of which have been tackled in earlier years.  

For more details - see Contact Information.


Virtual experiments for the Electrical Laboratory

mosfet.jpg (48029 bytes)

REFERENCE 2008-B-DMH-7 
SUPERVISOR Dr D M Holburn
EMAIL Contact Information 

This is a computer-based project. It concerns the development and evaluation of interactive applications to help in the teaching of electronics and microcircuit engineering at all levels, by providing tools to help visualise and understand key circuit structures. It's expected these will be multimedia-based, with animation employed where appropriate. Previous projects have developed very successful tools for visualisation of diodes, FETs and other structures, and these are now accessed world-wide.

You can see examples of what has been achieved in previous projects on the web (Flash player required), at:

Choice of environment and/or development language will be a key decision. The Java programming language facilitates a user interface with a wide range of graphical and other elements (including multimedia), as well as portability, and the use of the Internet will permit remote access to these applications from other sites. Other possibilities include Macromedia Flash.

Aspects of electronics that it's hoped to address are likely to include: bipolar transistor operation, AC circuits, op-amp circuits, radio receiver, MOSFET layout and structure, inverter propagation delay, input/output pad design, but this list is not exclusive.
Requirements: Good programming knowledge and interest in graphics and multimedia. Preferred: Experience of HTML, Java or similar programming.

For more details - see Contact Information.


Solid-state radio receiver - a project for the Part IA Laboratory

REFERENCE 2009-B-DMH-6 
SUPERVISOR Dr D M Holburn
EMAIL Contact Information 

This project concerns the development of an experimental project which will form a part of the updated Part IA Electrical Laboratory.  It aims to produce a number of electronic building blocks based on the devices, circuits and concepts studied in the IA course material to produce a modular broadcast radio receiver capable of demonstrating amply the principles of operation and allowing an insight into the ways in which performance can be optimised, energy consumption minimised and manufacturing costs maintained competitive.  

The receiver will comprise radio frequency and audio frequency amplifiers based on MOSFETs and op-amps, resonant tuning circuits, diode detector, energy-efficient power supply based on rechargeable cells.  It will be developed in a modular form, using printed circuit technology, with test points to allow for monitoring, and allowing for flexibility in the interconnection of the modules.  The Department's Electronic Development Unit will assist with the fabrication of circuit boards.  A low-power local source of broadcast signals will also be developed to allow comparisons of sensitivity, fidelity, etc.

The project will involve the use of circuit simulation tools like pSpice, not only to guide the development, but to provide teaching material that will be available alongside the experiment and to facilitate 'what-if' investigations during the lab session.

This project will best suit someone with an interest in electronic circuits, and who is also interested to develop skills in electronic design, circuit board layout, electronic fabrication, and circuit modelling.  

For more details - see Contact Information.


Development of Test-Bench for Electron Back-Scattered Detectors

REFERENCE 2009-B-DMH-7 
SUPERVISOR Dr D M Holburn
EMAIL Contact Information 

Back-scatter electron detectors are critical components in scanning electron microscopes and other electron-beam technology instruments.  They typically comprise an array of large-geometry large silicon diodes, often in a symmetric four-quadrant annular construction

A test-bench is required for characterising such diodes in terms of their bandwidth of operation.  Although in normal use they respond to incident medium-energy electrons, in terms of bandwidth, a comparable response may be obtained using a pulsed optical source.  This project involves the development of such a source, based on a fast pulsed LED (suitable types are available for communications applications), with suitable amplifier and signal measurement electronics.  Appropriate control circuitry will also be required to develop variable pulsed waveforms from 20-100MHz to drive the LED, and to assess the signal obtained from the detector diodes in terms of its strength and frequency response.

This project will best suit someone with an interest in optics and electronic circuits, and who is also interested to develop skills in electronic design, circuit board layout, optical systems, electronic fabrication, and circuit modelling.  It will be run collaboratively with Carl Zeiss SMT, a world- leading manufacturer of scanning  electron microscopes, who are partners with the Centre for Advanced Photonics and Electronics (CAPE) at the Department of Engineering.  

For more details - see Contact Information.

Useful Links

http://en.wikipedia.org/wiki/Scanning_electron_microscope#Detection_of_backscattered_electrons

http://www.smt.zeiss.com/C1256E4600307C70/EmbedTitelIntern/PI_EVO_Five_Segment_ZEISS_Backscattered_Detector_HR/$File/PI_EVO_Five_Segment_ZEISS_Backscattered_Detector_HR.pdf


 

A Computer-Based Training Tool for Marine Radar

REFERENCE 2008-B-DMH-8 
SUPERVISOR Dr D M Holburn
EMAIL Contact Information 

Marine radar is an enormous asset at sea when suddenly a bank of fog reduces visibility. Falling costs have meant that even modest craft can have radar installed. However, the 'jumble' of smudgy images normally seen is often very difficult to interpret, and the inexperienced user also finds adjustment of the instrument a great challenge, especially when conditions are difficult. A means is needed for crew to receive training in the use of radar without having to put to sea to receive it.

This project aims to develop a personal computer-based simulator for training in the use and operation of marine radar systems, ideally based on a Web browser. The simulator should emulate most of the functionality found on a modern marine radar as well as providing control over sea state and weather and other conditions. There are a couple of basic systems available commercially, but these are restricted to fixed scenarios and coastal regions. The aim is to explore the possibility of using readily available sources of cartography, (e.g. Google Earth, Yahoo Maps, or (maritime sources) C-Map and Navionics, interpreting this to generate plausible radar images. In this way it will be possible for the 'trainer' to be based at a wide range of coastal locations, e.g. Dover Harbour, Portland Bill, Felixstowe Docks, Corryvreckan .. limited only by the cartography available. This will call for a degree of understanding to be gained of the process by which a real radar image is formed. 

This is a software engineering project which will suit someone with an interest in web-based technologies e.g. Flash, HTML, JavaScript, PHP and Java, and their application to yachting and navigation. 

For more details - see Contact Information.


High Performance 1 GHz Voltage Controlled Oscillator

REFERENCE 2006-B-DMH-5 
SUPERVISOR Dr D M Holburn, Mr J Jiang
EMAIL Contact Information 

Oakleaf is an ongoing collaborative research project investigating optical methods of extending high bandwidth networking to the home. One of the key components required is a high performance voltage-controlled oscillator which generates signals used in mixers (frequency converters). 

This project will entail a study of cutting-edge theory and practice in the design of VCOs, based on an industrial-strength 0.18 micron CMOS IC foundry process, to develop numerical models to help understand the key design factors. 

The principal objectives will be to investigate models and physical layout for a circuit intended to operate at approximately 1 GHz, with acceptably low phase noise and a sufficient tuning range. Layout can be undertaken using Mentor Graphics IC Station, which also provides means for simulating the designs in order to predict their performance.

For more details - see Contact Information.


REFERENCE 2005-B-DMH-1
TITLE Managing Academic Questionnaires on the Web 
SUPERVISOR Dr D M Holburn 
EMAIL Contact Information 
ROOM 
INDUSTRIAL DESCRIPTION 
The convergence of computing and communications technologies is revolutionising every aspect of our lives, even in the University of Cambridge! A responsibility which the University takes very seriously is ensuring adequate opportunity for feedback from students on all aspects of College and University provision, and that appropriate arrangements are in place for responding to and reviewing such feedback. In most Colleges this currently relies on circulating paper questionnaires with a mixture of multiple-choice and free-form inputs. Processing and reviewing is carried out by Tutors and Directors of Studies on a confidential basis, and is currently a slow and tedious operation because of the volume of paper involved. 

The aim of this project is to explore how data of this kind may be captured, filtered, stored and directed to the intended recipients in a more automated fashion, so making the feedback system more efficient and responsive. Questionnaires will be web-based and make full use of multiple-choice options and helpful prompts. Data should be stored securely with password protection, but with provision for review and printing out by the student. Appropriate utilities will be required to filter and present the collected data in a variety of useful ways. The system needs to be largely platform-independent in order to be compatible with the wide range of target computing systems across the University & Colleges. 

The project will include reviewing the available technologies and selection of those most suited for the task. It will involve a study of the requirements of the questionnaire and the best ways of eliciting useful information. Web-based software (web pages and scripts) will be developed to allow secure capture of data to a suitable database. Utilities will be written in a suitable language to access and manipulate the stored data.

This project will best suit someone who has general programming experience and ideally some aptitude for web/database programming and presentation technologies - for example, html, php, MySQL.

There's a sample questionnaire as used in 2002-3 at: 

http://www.cai.cam.ac.uk/students/supervisions.php


Virtual Scanning Electron Microscopy

REFERENCE 2006-B-DMH-1 
SUPERVISOR Dr D M Holburn, Mr Geoffrey C Martin
EMAIL Contact Information 

Scientific instruments have become increasingly complex and yet greatly more versatile with the advent of computer power. This is particularly true of the Scanning Electron Microscope (SEM). Ease of use is now key to the commercial success of modern SEMs. 

The SEM has evolved from an essentially mechanically operated device, to one entirely controlled using a PC, hiding the complexity of the instrument behind an easy-to-use interface. As a result, users' understanding of the underlying science and principles of microscopy has declined. Meanwhile, improvements in computer power have turned the Internet into an ideal medium for delivering educational content, not least to the SEM operator's desktop.

Virtual SEM (VSEM), an ongoing project in CUED, aims to develop web-based teaching and training software relevant to all situations where SEMs are used, or their theory taught. The concept includes a training simulator, educational course modules, and an encyclopaedia of the SEM. These work together to deliver effective teaching & training to the user's web browser.

This project focuses on development of the SEM encyclopaedia. The student will begin by gaining an understanding of the SEM. He/she will then evaluate appropriate web-based technologies. These will subsequently be used to develop sections of the encyclopaedia to interface with existing elements.  You can see some examples of what has been achieved so far in the project on the VSEM web, at:

http://www.virtualsem.com

A software engineering project, this will suit someone who has experience and/or an interest in learning web-based technologies including Flash, HTML, JavaScript, PHP, Java & MySQL. 

For more details - see Contact Information.


3D Reconstruction of SEM Semiconductor Images

REFERENCE 2006-B-DMH-3 
SUPERVISOR Dr D M Holburn, Mr B C Breton
EMAIL Contact Information 

Focused ion beam (FIB) instruments and scanning electron microscopes (SEMs) are key tools in the semiconductor industry. FIBs are used to etch devices and surfaces, whereas SEMs can provide imaging on nanometre scales. Recently dual-beam instruments have been developed which combine FIB and SEM technologies, enabling a sample to be successively etched and imaged in the same machine. This computer-based project will take successive SEM images of "slices" through a semiconductor device and reconstruct these into a 3-D visualisation of the original device. 

This project will be run in collaboration with Carl Zeiss SMT, a multinational company based in Cambridge, who design and manufacture dual-beam instruments as well as scanning electron microscopes and other types. Carl Zeiss SMT will provide an introduction to dual-beam technology and sample images for development and testing purposes. 

This project calls for some programming experience (in MATLAB and/or C++ for the PC) and an interest in digital image processing - any experience in this area through appropriate modules from group F will be highly beneficial. 


Electron Detection – The Shape of Things To Come? 

REFERENCE 2008-B-DMH-4
SUPERVISOR Dr D M Holburn 
EMAIL Contact Information 

The scanning electron microscope (SEM) is one of the most versatile instruments ever developed for observing and measuring on the microscopic and nano-scales. An integral component of every SEM since the 1960s has been the secondary electron detector, developed by Everhart and Thornley in the Department of Engineering. The Everhart-Thornley detector collects the electrons emitted by a sample when struck by an electron beam and transmits a resultant signal through further hardware until it is eventually processed into the detailed image that appears on the SEM’s monitor screen.

One way of improving the performance of this detector may involve changing the geometry of the collection electrodes. This project would involve investigating the geometry of existing collection electrodes in order to measure their performance and producing a computational model to propose geometries that would offer greater sensitivity and resolution. The second half of the project would then involve the design, prototyping and testing of one or more of the candidate geometries.

This project would be run in close collaboration with Carl Zeiss SMT, a leading global manufacturer of scanning electron microscopes, and an industrial partner of the Centre for Advanced Photonics and Electronics (CAPE) at the Department of Engineering. Carl Zeiss would assist with an introduction to the SEM and providing access to different versions of the Everhart-Thornley detector.


Photodiode Detection – The Light Fantastic

REFERENCE 2008-B-DMH-5
SUPERVISOR Dr D M Holburn 
EMAIL Contact Information 

For nearly sixty years, the scanning electron microscope (SEM) has been one of the most versatile instruments ever developed for observing and measuring on the microscopic and nano-scales. It has been and is widely used in many disciplines of science and many fields of industry. Its performance has steadily improved and instrument manufacturers continue to devote substantial effort to finding new ways to make it better as microscopists find ever more challenging tasks that need the SEM.

Critical to the production of many high-quality SEM images has been the Everhart-Thornley detector. This device collects the electrons emitted by a sample when struck by the electron beam and transmits a resultant signal through further hardware until it is eventually processed into the detailed image that appears on the SEM’s monitor screen.

One possible means of improving the performance of the SEM might be to use a system of photodiode(s) to detect and collect the electrons. This project would involve adapting an existing Everhart-Thornley detector to use photodiodes instead, and would focus on prototyping and testing the modified system, and comparing the results with a standard Everhart-Thornley detector.

This project would be run in close collaboration with Carl Zeiss SMT, a leading global manufacturer of scanning electron microscopes, and an industrial partner of the Centre for Advanced Photonics and Electronics (CAPE) at the Department of Engineering. Carl Zeiss would assist with an introduction to the SEM, supply a standard detector suitable for modification, and assist with the implementation of a suitable test rig.

For more details - see Contact Information.


CMOS-based Cathodoluminescence Detector for the SEM

REFERENCE 2011-B-DMH-5
SUPERVISOR Dr D M Holburn 
EMAIL Contact Information 

For nearly sixty years, the scanning electron microscope (SEM) has been one of the most versatile instruments ever developed for observing and measuring on the microscopic and nano-scales. It has been and is widely used in many disciplines of science and many fields of industry. Its performance has steadily improved and instrument manufacturers continue to devote substantial effort to finding new ways to make it better as microscopists find ever more challenging tasks that need the SEM.

SEMs can be fitted with high-performance cathodoluminescence (CL) detectors, such as the Gatan Chroma-CL, to image fluorescent materials. But such detectors are both very bulky and very expensive. Hamamatsu has recently launched a CMOS-based mini-spectrometer (C10988MA). This could potentially be used on an SEM to make a small, low-cost 'Chroma-CL' detector. While the sensitivity, noise levels, and spectral resolution would not be as good, they may be acceptable for certain applications such as true-colour imaging or differentiating between fluorescent biomarkers.  There are a number of areas that will need to be looked at: 1. Feasibility - will the light levels in a typical SEM be high enough to take images? - what SNR will be achievable? - can this be improved by varying the clock frequency of the sensor? - how do the time scales relate to scanning speeds of an SEM?. 2. Electronic interface - Hamamatsu produce an evaluation board to test the sensor (C11351) but we would have to produce our own custom circuit based on this for a fully-functioning detector - the specification of this board would be a key activity 3. PC interface - Hamamatsu provide basic test software, but more code will be needed to  convert the information from the detector into an image on the PC..

This project would be run in close collaboration with Carl Zeiss NTS, a leading global manufacturer of scanning electron microscopes, and an industrial partner of the Centre for Advanced Photonics and Electronics (CAPE) at the Department of Engineering. Carl Zeiss would assist with an introduction to the SEM, supply a standard detector for evaluation, and assist with the implementation of a suitable test rig.

This project will suit someone with wide-ranging interests in instrumentation, optics, electronic design and software coding.

For more details - see Contact Information.


Contact Information


Page last updated: 20:41 on Wednesday, 11 May 2011