Our Unit Converter

The ESI Unit converter allows you to quickly and easily access a conversion tool to work out your preferred unit of pressure measurement wherever you may be. Whether out on-site or in the office.

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Download the ESI-USB© Software

The ESI-USB© software allows you to connect your ESI transducer to your laptop or PC and be up and running monitoring pressure data within ten minutes. The software auto-updates and is compatible with Windows 8, 10 & 11.

The Spooky smarts to Silicon-on-Sapphire technology!

Silicon on Sapphire is a technology that is part of the Silicon on Insulator (SOI) family. It is a semi-conductive structure that is created through a process known as heteroepitaxy – where an epitaxial (or crystal growth) layer is deposited on the surface of a different material – in this case a thin layer of silicon is physically placed onto a sapphire wafer at a very high temperature and bonded.

The Sapphire

The Sapphire wafers used in SOS technology are unlike the naturally occurring gemstones that are found in the ground. They are grown as a single gem in a highly controlled laboratory environment, ensuring no impurities or imperfections in the finished structure.

The crystal is then cut at roughly a 60° angle. This is what is referred to as the “r-plane”, a term used to define the angle of the gemstone cut.

The Bonding

This is where it gets really interesting… Because of the precise angle of the cut, Sapphire wafers have extra Oxygen atoms that almost mirror the spacing of Oxygen atoms found in the plane of Silicon. This incredible natural symmetry allows the Oxygen atom in the Silicon to bond to the Oxygen atom in the Sapphire, creating a Silicone-Oxygen, or SiO2 bond. It is this compatibility between the plane of Sapphire and plane of Silicon that enables the SOS technology.

But what does SOS Technology Do for ESI?

An SOS structure is essentially a semi-conductive surface. It provides the base for circuit and sensor manufacturing that is durable, resistant to heat and radiation, and performs consistently under varying levels of stress.

A Wheatstone bridge is formed in the Silicon during the manufacturing process of SOS sensors. This is a circuit used to measure electrical resistance between the two “legs” of the circuit.

Strain Gauges are used in place of resistors to provide a “difference measurement”. So when the sensor is attached to the diaphragm it will be able to accurately indicate any strain change in the metal whilst pressure is applied. This can then be converted to a voltage change in order to transmit pressure data. That, plus the insulating nature of the Sapphire base, protecting the strain gauges, and the lack of bonding agent between the two elements ensures a highly reliable and accurate sensor with minimal hysteresis under stress. The elasticity of the Sapphire element also provides the structure with great repeatability over an extended period of time.

It is for this reason the highly stable, highly accurate SOS sensor technology is a popular choice within aerospace and aeronautic applications.

So you see? It’s not WITCHCRAFT at all… just some very clever SCIENCE!

Contact us

For more information on our Silicon-On-Sapphire products visit our website or call our sales team on (01978) 262255