Electron microscopes have a wide range of applicability and material science is a prominent application. However, electron microscopes can be disrupted by all forms of environmental noise which can then limit the quality of data received and in some cases, render the instrument unusable.
In this interview, Reid Whitney, Director of Sales and Marketing from Herzan, talks to AZoM about learning to Optimize Electron Microscopes and how to solve environmental noise concerns.
What are the typical applications for Electron Microscopes?
Electron microscopes have a wide range of applicability, with specialized iterations addressing unique application requirements. Material science is a prominent application often pursued by electron microscopy users, researching materials to improve diverse industries that have an immediate impact on everyday lives.
In addition to materials science, the following applications are common among electron microscopy users:
- Oil and Gas
- Minerals and Mining
- Industrial Manufacturing
- Life Sciences
What forms of environmental noise commonly affect electron microscopes?
Electron microscopes can be disrupted by all forms of environmental noise, but are most susceptible to vibrations and magnetic fields. Acoustic noise can also impact the imaging of an electron microscope, but most manufacturers are able to design the electron microscope in such a way that shields from the effects of acoustic noise.
Electron microscope manufacturers often evaluate the effects of environmental noise on their instrument, resulting in a list of specifications for the operating environment to adhere to that states the maximum allowable vibration, acoustic, and EMI noise. These noise levels are often characterized by a site survey, which then informs whether mitigation techniques are required or if a new lab is advised.
How does environmental noise affect the user experience of an electron microscope?
Environmental noise can limit the quality of data retrieved by an electron microscope and in more severe cases, render the instrument unusable. When this occurs, research is delayed and the cost of a project increases as the project timeline expands. Fortunately, electron microscope manufacturers are aware of this issue and take necessary precautions to understand the operating environment prior to installing an electron microscope to prevent unwanted downtime of the instrument.
The most common situations where an electron microscope can experience unanticipated noise include:
- New, noise-generating equipment are introduced into the environment
- New construction work begins outside or adjacent to a lab
- The lab is required to move locations, where there are undesirable noise conditions.
Figure 1. SEM Image Affected by AC Fields, Without SC System Figure 2. SEM Image Affected by AC Fields, With SC System
What approach does Herzan take to solving environmental noise concerns?
The first step is to understand the extent of the noise and how that corresponds with the instrument manufacturer's specifications. To understand the extent of the noise, we advise a site survey be performed at the customer’s location to fully characterize the noise in the corresponding lab environment.
The second step is to identify whether mitigation techniques can be employed to remove the noise affecting the instrument. Common mitigation techniques include:
- Removing noise generating equipment from the room
- Re-locating the microscope to a quieter operating environment
- Providing environmental solutions for the noise generating equipment (i.e. acoustic enclosures for noisy chillers and pumps, sorbathane feet for vibrating equipment, etc.).
The third step is to recommend an environmental isolation system in the event mitigation techniques were unsuccessful.
- Vibration noise: AVI Series Platform
- Acoustic noise: EM Acoustic Enclosure
- EMI Noise (AC and/or DC Fields): SC Magnetic Field Cancellation System
Figure 3. Environmental Solutions from Herzan
Focusing in on one of the more disruptive forms of environmental noise: If excessive levels of EMI are present, what should a user do?
Excessive EMI noise is easy to identify as it can directly impact the quality of imaging for an electron microscope. AC fields are often represented as small, jagged teeth along the perimeter of the image, whereas DC field are often shown as a wavy image or stitching errors in the case of electron beam lithography.
When the presence of EMI noise is certain, it is important to perform a site survey to gain a full understanding of the noise levels of the room. With a full understanding of the noise in the room, the correct solution can be easily decided.
From Herzan’s product range, which product would you select as a solution for EMI noise? Why?
EMI noise can be resolved with different solutions depending on the type of noise limiting the instrument. For electron microscopes, AC and DC fields within a narrow frequency range (0 – 60 Hz) are of most concern as they can alter the quality of data being received. If AC fields are the only concern in the environment, the SC22 is the correct solution. If DC fields are present in the environment and limiting the microscope, the SC24 is the correct solution.
The difference between the two solutions is simple: one addresses AC fields and the other addresses AC and DC fields. The design and overall functionality between the two systems is similar, but differentiated to allow users to know which one best serves the needs of their environment.
The easiest way to decide the correct SC System for their environment is by reviewing a site survey characterizing the room and comparing that data with the instrument manufacturer’s environmental specifications for AC and DC fields. With that information in hand, a user can know the individual frequencies where their environment exceeds specification, allowing them to understand the correct solution to mitigate the noise.
Figure 4. SC System Diagram with Scanning Electron Microscope
Are there other products or services available from Herzan that can benefit electron microscopy users?
Herzan has developed a complete range of products and services tailored for electron microscopy users so they can feel confident when addressing issues affecting their instruments. Some common products and services not already discussed include:
Needing to raise the instrument for installation
Instrument lifting mechanism
Unknown environmental noise
Site survey tools or service
Height restriction for TEM acoustic enclosure
False-floor sub-frame and support structure
Earthquake restraint required for vibration isolation platform
Earthquake restraints integrated with the AVI platform
HT Tank causing vibrations
Vibration isolation platform for HT Tank
And many more
If there are other complex requirements affecting a user’s electron microscope, Herzan’s engineering team will be happy to review and help define a solution.
Where can our readers go to find out more?
Readers wanting to learn more about our environmental solutions for electron microscopes can visit http://www.herzan.com/solutions-for-electron-microscopy.html, which will guide them to several resources including solutions guides, user testimonials, and performance comparison images. This collection of information can help readers feel reassured when facing environmental noise concerns, as they know there are solutions that work and have been proven to dramatically improve the imaging of electron microscopes in the nosiest environments.
About Reid Whitney
Reid Whitney started his career in the field of business analytics, focusing primarily on revenue optimization through targeting counterfeit goods.
Today Reid leads the business development activities for Herzan, primarily governing the sales and marketing strategies and working with team members to elevate the user experience for customers.
Disclaimer: The views expressed here are those of the interviewee and do not necessarily represent the views of AZoM.com Limited (T/A) AZoNetwork, the owner and operator of this website. This disclaimer forms part of the Terms and Conditions of use of this website.