• Slide Title

    The NEW SC24 Field Cancelling System

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  • Over 70 years experience

    practical expertise in SEM
    and e-beam tools

  • SC11 Analysis System

    In-depth analysis from the
    all-in-one, easy to use system

  • Slide Title

    The NEW SC26

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Analysis Systems

Combining the measurements and analysis of magnetic fields, vibrations and acoustics into one compact, easy to operate system, Spicer Consulting's SC11 is the simplest way to gain accurate usable data from site surveys for SEMs and similar sensitive equipment.

Field Cancelling

Spicer Consulting field cancelling systems can stabilise the ambient magnetic field to restore the resolution and accuracy of an electron beam tool.

Discover our range of  f ield cancelling systems, including the latest SC24 , SC22 and SC26 .

Consulting & Installation

With over 70 years of combined experience providing practical expertise in SEM and e-beam tools, we provide a wide range of consulting services. 

From installation support, through to the modelling of magnetic fields for a custom installation, we have the expertise to help you.

Latest

Knowledge Base

By spicerconsulting 27 Jan, 2017
We were asked whether moving gas cylinders on the floor above a large TEM would cause a problem with its magnetic field environment. We made measurements of the DC field fluctuations at different positions as a large gas cylinder was wheeled past on a trolley. The results show that a non-uniform field fluctuation was created by the cylinder, which would exceed the specifications of the microscope. It would require a dual magnetic field cancelling system to bring the field back into specification. It should be noted that the cylinder was a standard type used in many laboratories, but we only made measurements for one cylinder. Other cylinders may give different levels of field.

Introduction

A large high resolution TEM with monochromator and energy analyser can image with sub-Angstrom resolution, but is very sensitive to magnetic fields in the environment. Typically the field is required to be stable to within 30 nT Pk-Pk, but some models have tighter requirements.

We were asked whether moving gas cylinders on the floor above a large TEM would cause a problem with its magnetic field environment, so we decided to make some measurements. It was not convenient to measure the field below the cylinder, so we measured the field above it.

Procedure

The steel gas cylinder was made to BS 5045-1. It was 1.5m long and 0.22m diameter. It was found to be slightly magnetised, with fields up to about 4 times the Earth’s field on the surface of the cylinder. No special effort was made to magnetise or de-magnetise the cylinder, so it may be regarded as typical. It was placed on a standard steel trolley designed to carry gas cylinders.

A Spicer Consulting 3-axis DC sensor was placed at various different heights. The cylinder trolley was pushed under the sensor for a distance of 5m in the Y direction relative to the sensor. The Earth’s field is X=120, Y= 140, Z=-440 mG, relative to the sensor. The sensor was reset each time to remove the Earth’s field from the measurement.

The SC11 Chart Recorder was used to chart the magnetic field waveform in 3 axes. The resulting waveforms were extracted from the chart recorder results and plotted using SCplot. The peak to peak change reported by SCplot was adjusted to remove the AC (50 Hz) that broadens the trace on the chart. The height of the cylinder was subtracted from the height above ground to obtain the distance from the cylinder. The results are summarised in Table 1 and Chart 1 below.

Results
By spicerconsulting 17 Nov, 2016

Spicer Consulting is pleased to announce the new SC11/AC sensor. This new sensor is for use with the SC11/SI and is not for use with cancelling systems. It has the same magnetic field bandwidth and range as the SC11/Basic sensor, but no built-in inputs. It gives the SC11/SI the same AC field measuring capabilities as the SC11/Basic. 


We no longer recommend any other AC sensor for use with the SC11/SI. If you would like to know which magnetic field sensor you should use, check out our guide .

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