David P Langstaff
University of Wales, Aberystwyth
Gilfach, Allt Glais,
Marital status: Married, 2 sons
Place of Birth: London, UK
Full UK Driving License (No endorsements)
1978 - 1981
B.Sc.(Hons.) Electronic Engineering. Upper Second.
Dissertation project on construction of a semiconductor test/characterisation system based around IEEE-488 bus controlled instruments.
1994 - 1998
University of Wales, Aberystwyth
The Development of an Ion Counting Detector Array
My career has been focused on the design, development and fabrication of silicon integrated circuits. I was fortunate to work as a post graduate in the microelectronics fabrication facility at Southampton University for a number of years before coming to the Physics Department at Aberystwth.
During my time at Southampton I was concerned with a number of different aspects of silicon integrated circuits, from the day to day operation of a high precision lithography machine to the layout of mask data for gate array circuits for undergraduate projects. As well as the in-house standard process offered by Southampton, commercial work for Cableform Ltd. gave me experience of designing into a third party fabrication line and the commercial pressures of an industrial project. As part of Southampton’s S.E.R.C. funded Design Centre, I was responsible for liasing between external customers and the fabrication line, visualising how non-standard fabrication steps and artefacts could be incorporated into the standard processes offered. During this time I made extensive use of CAD packages for a number of different tasks, from process and circuit simulation to mask layout, design rule checking and circuit verification. Additionally I have programmed in a variety of languages in order to write utilities to overcome shortcomings in the available design packages.
In 1990 the research post at Aberystwyth provided an ideal opportunity to focus my experience on a demanding project to develop a high resolution array of detectors and counters on a single piece of silicon for use in mass spectrometry. The array operates as an extremely sensitive imaging device, capable of counting single ions, photons or electrons with high positional accuracy. As well as the design of the silicon circuits which form the heart of the detector, I have also designed ceramic hybrid circuits upon which the detector is mounted, circuits to interface the detector to a PC and software to control the detector and analyse the results. I have been involved in incorporating the detector into different mass spectrometers, overcoming problems in vacuum compatibility and ion optics and devising experiments to evaluate its performance. I am currently responsible for detector system in the REES project including the design of the array itself.
I have used my engineering and electronics background extensively in the taught modules I have contributed to. The discipline of silicon fabrication encompasses a wide range of topics relevant to physics, from crystallography and materials science to vacuum technology, ion and electron beams. The software packages use techniques highly relevant to modern physics, finite element analysis, modelling, visualisation and the solution of complex systems of differential equations are all relevant to a physics undergraduate. I already use examples of analysing data retrieved from the array to illustrate data handling and curve fitting as part of the PH36010 numerical methods module.
1977 - 1978
Marconi Radar Company
Graduate Apprentice on E.I.T.B. accredited training scheme.
· Drawing Office.
· Test Equipment & Calibration.
· Production Engineering.
· 3-phase control systems.
· Computer hardware debugging & fault-finding.
1981 - 1990
Southampton University Microelectronics Group
Research assistant with Wolfson Industrial Unit.
Car Lights Monitor (1981-1983)
A custom silicon circuit to monitor light failure for the Cableform Ltd.. Responsible for:
· Testing previous version of circuit to determine failure modes.
· Design, simulation and mask layout of new circuit.
· Liaison with Motorola process engineers.
· Wafer and device testing, including high voltage and load-dump testing.
· Liaison with Cableform Ltd. on module construction and application.
Paper on circuit presented at Meeting on Mixing Analogue and Digital Integration, Organised by I.O.P. & I.E.E., 26 Feb. 1987.
Custom Dosimeter Devices (1982-1985)
Supply of custom dosimeters to Fulmer Research Ltd.
· Supervising device manufacture on wafer fabrication line.
· Wafer and encapsulated device testing.
· Process adjustment for optimum device characteristics.
S.E.R.C. Design Centre (1984-1987)
Provision of support for S.E.R.C. research customers wanting access to silicon processing facilities at Southampton.
· Liason between S.E.R.C. customers and fabrication line.
· Design of specialised silicon structures & fabrication artefacts.
· Integrating ‘unusual’ silicon processing and etching requirements with existing standard processes.
MSc. Microelectronics Course & Short Courses for Industry (1986-1989)
· Provision of CAD support.
· Organising practicals and demonstrations.
Contributed 2 chapters to book from course notes “VLSI: Circuits and Systems on Silicon”.
P1085 Transputer Project (1987-1988)
Worked on the development of the Transputer Supernode project funded as part of the Esprit programme. Responsible for test rig design & communications facilitation.
Electron Beam Microfabrication Facility (1988-1990)
Operator and CAD support for Cambridge Instruments Electron Beam Microfabricator installed in the microelectronics facility.
· Overseeing on-site acceptance tests.
· Development of a Helmholtz coil system to screen instrument from stray low-frequency magnetic fields.
· CAD support & data preparation
· Machine & process optimisation and operations.
1990 - 1995
University of Wales
Research assistant with Integrated Sensors research Group.
Ion Counting Detector Array
Link project in conjunction with VG Analytical Ltd. (Wythenshawe).
· Detailed design and implementation of a custom detector circuit fabricated in cMOS technology for mass spectrometry and particle physics applications.
· Liaison with process engineers at Hughes Microelectronics Europa Ltd. to optimise etching and step coverage on non-standard process layer.
· Design of ceramic substrate & PC interface circuitry.
· Test, debugging and characterisation of detector in vacuum systems.
· Implementing control software in Borland Pascal/TurboVision.
Further Work with Ion Counting Detector Array
· Visits to JPL Pasadena for evaluation of detector array in conjunction with M. Sinha (Caltech/NASA).
· Design of fibre-optic isolated interface for detector.
· Re-implementation of control software in Borland Delphi.
Administration work within Physics department
· Responsible for co-ordination of marking and distribution of marks for continuous assessment sheets.
· Designed spreadsheet for storage/processing of marking data.
Lecturing within Computer Science Department
· Wrote and presented ½ module CS10110 – An Introduction to PC Hardware.
Lecturing within Physics Department
· Wrote and presented 1/3 module PH17010 – Concepts in Physics.
2001 - 2003
Post Doctoral Research assistant.
Real Time Electron Energy Spectrometry
· Transferring design of detector array to small feature size cMOS technology.
· Testing completed arrays.
· Specification of array controller
· Specfication and design of ceramic modules
· Programming of data collection software using Labview
· Characterisation of array/microchannel plate combination.
Lecturing in Physics Department
· Rewrote PH36010 numerical methods module to incorporate MathCAD, includes lecture notes, slides, lab handouts and worksheets.
· Wrote and presented part of PH15010 laboratory module dealing with basic use of MathCAD for first year students.
1995 - 1997
Augusta Technology Ltd.
Senior Systems Engineer.
Augusta Technology Ltd. was a UWA startup company, operating from the Aberystwyth Science Park and engaged on a number of projects ranging from hardware decoders for fight data recorders to database applications. I was originally employed for electronics assembly work on the flight recorder interface circuit and rapidly took over circuit and board level design, hardware debugging and FPGA programming for the project, as a result of this I was promoted to Senior Systems Engineer within the company.
Following promotion, I was engaged on the childcare database project, which gave me experience of project management. At this time I was also invited to contribute to board meetings of the company which gave me an insight into the w
In 1997 following closure of the company I purchased the goods and chattels of Augusta Technology from the receiver in order to continue the flight recorder and childcare database projects as a private consultancy.
Flight Recorder Interface Project
The Flight Recorder Interface project comprised a number of electronics modules designed to convert the signals from an analogue flight data recorder into data packets and supply these to a laptop computer. The units were based around an embedded 68302 processor using analogue electronics for signal conditioning and FPGAs for decoding the datastream.
Responsible for :
· Board layout
· Overseeing board assembly
· FPGA programming
· Systems integration
· Provision of customer support
· Hardware and software debugging
· Advising customer on EMC compatibility issues
The Childcare database was an application for disseminating information about childcare providers throughout Wales. When I joined the project, information about childcare providers was collected in an office system and distributed via a public terminal application, both the office system and terminal application being written in visual basic. Following discussion with the customer (Chwarae Teg) I re-wrote the office system in Microsoft Access and oversaw a student writing the public terminal application as a Delphi program.
· Liaison with customer for revised project specifications
· Overseeing writing of database application in Delphi
· Writing office system in Microsoft Access.
Contributor to background notes for microelectronics system course.
Eglwys-Fach, Machynlleth, Powys
Custom software for estimating visibility of wind turbines.
Program to interface with digitising tablet and calculate profile cross-section of terrain from OS map data.
Gilfach Technology 1997-2001
Proprietor of private consultancy
Following the closure of Augusta Technology in 1997, I continued to offer customer support for the flight data recorder and childcare database projects I had previously been engaged on.
Flight Recorder Interface Project
· Maintaining units returned for repair
· Brining units up to current mod state
· Creation of web site for Chwarae Teg
· Maintaining database of 1500+ childcare providers throughout Wales
· Maintaining list of database end users.
· Production of database distribution disks on CD-ROM & floppy disk
· Distribution of quarterly updates to end users.
· Attending regular meetings with customer and end users.
· Re-writing system to use web browser technology.
I have experience with the following software packages and operating systems:
DOS / Windows
Unix / Linux
Borland Pascal (v7.0) / TurboVision/Delphi
Turbo Basic / Visual Basic
Spice (Various versions)
Silvar-Lisco SL2000 CAD suite
Cadence Framework CAD suite
Tanner Tools IC Design Package
ISHM Conference – Southampton UK Sept 92
Langstaff, D. P. (1992). “Development of a Multichannel Charge Transducer.” International Society for Hybrid Microelectronics, Southampton.
Prague Week of Doctoral Students ’94.
Langstaff, D. P. (1994). “Some Experiences in Using an Ion Counting Detector Array.” Week of Doctoral Students, Charles University, Prague.
K.Birkinshaw, D.P.Langstaff, "The ideal detector", 22nd annual British Mass Spectrometry Society meeting, Swansea, (1996).
Mars Exploration 1999
K.Birkinshaw, D.P.Langstaff, D.J.Narayan, G.N.Greaves, "An Integrated Detector System" International symposium on the Mars Exploration Program and Sample Return Missions, Poster P1/S14(2), Paris 1999.
K.Birkinshaw, D.J.Narayan, D.P.Langstaff, G.N.Greaves, "A detector array system on a single silicon chip – uniformity correction", SPIE proceedings (Detectors for crystallography and diffraction studies at synchrotron sources), 58-65,3774(1999)
Langstaff, D. P. (2000). “Linearity of an Ion Counting Charge Detector Array Over Several Orders Of Magnitude.” Federation of Analytical Chemistry and Spectroscopy Societies, Nashville, TN.
K.Birkinshaw, D.J.Narayan, D.P. Langstaff, "The correction of non-uniformity and MCP non-linearity in detector arrays", Paper, FACSS, Nashville, September 2000.
K.Birkinshaw, D.P.Langstaff, "Mass Spectrum Measurement using a Focal Plane Array of Counters on a Silicon Chip", invited paper, Pittcon 2002, New Orleans, 2002
Birkinshaw, K., D. P. Langstaff, et al. (2002). Deconvolution of Spectra Measured by a 1D Position Sensitive Detector. Sixth Positon Sensitive Detector (PSD6) conference, Leicester, UK.
LANGSTAFF, D.P., "Automotive
Lights Failure Monitor", Meeting on Mixing Analogue and Digital
Integration, Institute of Physics, (1987).
LANGSTAFF, D.P. "Mapping
Algorithms To Silicon - Some Examples", "VLSI Circuits and
systems in Silicon", Brown, A.D. (Ed.), pp145-172, McGraw-Hill, (1990)
LANGSTAFF, D.P. "Alternative Design Styles", "VLSI Circuits and systems in Silicon", Brown, A.D. (Ed.), pp202-221, McGraw-Hill, (1990)
Birkinshaw, K. and D. P. Langstaff (1994). "Resolving Power of a Discrete Electrode Detector Array." International Journal Of Mass Spectrometry And Ion Processes 136(1): 71-83.
Birkinshaw, K. and D. P. Langstaff (1994). "Silicon Technology in Ion Detection - a High-Resolution Detector Array." International Journal Of Mass Spectrometry And Ion Processes 132(3): 193-206.
Langstaff, D. P., M. W. Lawton, et al. (1994). "A New Ion Detector Array and Digital-Signal-Processor-Based Interface." Measurement Science and Technology 5: 389-393.
Langstaff, D. P. and K. Birkinshaw (1995). "The Dependence of the Resolving Power and Sensitivity of a Discrete Electrode Detector Array on the Proximity of a Microchannel-plate Electron Multiplier." Rapid Communications in Mass Spectrometry 9(8): 703-706.
Narayan, D. J., D. P. Langstaff, et al. (1995). "Simulation of a Discrete Electrode Detector Array Performance." International Journal Of Mass Spectrometry and Ion Processes 149/150: 439-449.
Langstaff, D. P. (1995). Uniformity in an Ion Counting Detector Array. Sensors and their Applications VII, Dublin, Institute of Physics Publishing.
Birkinshaw, K. and D. P. Langstaff (1996). "The Ideal Detector." Rapid Communications in Mass Spectrometry 10: 1675-1677.
Hart, J., R. Bordoli, et al. (1997). A Study of Array Detection techniques applied to High Resolution SIR Mass Spectrometry (Poster Presentation). The 45th ASMS Conference on Mass Spectrometry and Allied Topics, Palm Springs, California, USA.
Sinha, M., D. Langstaff, et al. (1998). "Resolving Power Enhancement of a Discrete Detector Array by Single Event Detection." International Journal Of Mass Spectrometry and Ion Physics 176: 99-102.
Narayan, D., D. Langstaff, et al. (1998). "Microchannel plate electron multiplier calibration using a discrete detector array." International Journal Of Mass Spectrometry and Ion Physics 176: 161-166.
Langstaff, D. P. (1998). The Development of an Ion Counting Detector Array. Physics Department. Aberystwyth, University of Wales: 190.
Sinha, M. P., D. P. Langstaff, et al. (1998). "Resolving power enhancement of a discrete detector (array) by single event detection." International Journal of Mass Spectrometry 176(1-2): 99-102.
Langstaff, D. P. (1999). Applications of an Ion Counting Array Detector for Mass Spectrometry. Sensors and their Applications X, Cardiff, Institute of Physics Publishing.
Birkinshaw, K., D. J. Narayan, et al. (1999). Detector Array system on a Single Silicon Chip - Uniformity Correction. SPIE Conference on Detectors for Crystallography and Diffraction Studies at synchrotron sources, Denver, Colorado.
Langstaff, D. P. (2002). "An MCP-based detector array with integrated electronics." International Journal of Mass Spectrometry 215(1-3): 1-12.
Member of Institute of Electrical Engineers
Member of Institute of Physics
Faculty of Science – Physics Department CRS representative
Prof. H.A. Kemhadjian,
Aberystwyth Summer Fayre (1993, 1994, 1995)
Organiser and local authority license holder of a 1-day community arts festival in conjunction with Aberystwyth Town Council. Responsible for health & safety on site, grant applications, managing budget of c.£3500 & compliance with local authority license conditions.
IGER Nursery Parents Group (2000- )
I have been an active member of the parents group of the nursery where my eldest son attends, contributing to social and fund raising events.
maintained by email@example.com.