Tom joined the J.A. Woollam Company in 1999 in the Applications group. Since then, he has helped customers utilize ellipsometry for a wide range of applications, including infrared optical materials, optical properties vs. temperature measurements, as well as liquid cell, in situ and web coating process monitoring and control. He has also trained new customers on how to use their instruments and perform data analysis. Ellipsometry is a self-referencing technique that does not require reference samples to maintain accuracy. Samples smaller than the beam diameter can be measured because the entire beam does not need to be collected. Highly Accurate Measurement Two values are used to describe the optical properties which determine how light interacts with a material. They are generally represented as a complex number. The complex refractive index (ñ) consists of the index (n) and extinction coefficient (k): Absorptions in materials can be caused by electronic transitions, lattice vibrations, and free carrier absorptions, among other things. The nature of absorption resonances vary by material and are dependent on a variety of factors. For this reason, mathematical descriptions for absorbing materials are traditionally more complex. CompleteEASE features multiple tools for modeling absorbing films easily and efficiently. B-Spline Wavelength range…both the number and range of wavelengths that can be measured are important factors for how well an ellipsometer can solve thin film measurement problems.

Angle range…most samples can be measured with a single angle of incidence. Discuss with our engineers to see if your samples will require more angles – desirable for multilayers, anisotropic materials, and complex structures. Collect over 1000 wavelengths from the ultraviolet to the near infrared – all simultaneously. Fast Measurement SpeedIt added: "It was agreed centrally to have the divert in place but the customer did not know this divert was in place." The council officer added that the divert has now been removed. Synchronous rotation of two compensators provides high accuracy, high speed, and complete Mueller-matrix measurements. Achromatic Compensator Design* The event will be hosted by the Optoelectronics Research Centre (ORC) and the CORNERSTONE Silicon Photonics MPW (Multi Project Wafer) service at the University of Southampton. The ORC is one of the world’s leading institutes for photonics research. New achromatic compensator design with optimized performance over a wide spectral range. *patent pending Wide Spectral Range

J.A. Woollam within a user-friendly interface. Real-time ellipsometry data contains a wealth of information. Samples can be fully characterized before, during, If this was concerning to local people, the situation became more worrying earlier this year when Veolia applied for permission to expand its Garston operation even further. This time the company wanted to increase its capacity to 86,000 tonnes of chemicals per year - another significant jump. where the parameters for Amplitude (A), Broadening (B), Center Energy (E c), and offset (ε 1 off set) are also shown in the figure belowfor a typical Lorentz oscillator. The energy, E, is related to the frequency of a wave, n:A spokesperson for Liverpool Council said comments submitted on the planning application had been received and taken into account in assessment of the proposal. Maxwell’s equations must remain satisfied when light interacts with a material, which leads to boundary conditions at the interface. Incident light will reflect and refract at the interface, as shown in the figure below. The angle between the incident ray and sample normal (θ i) will be equal to the reflected angle, (θ r). Light entering the material is refracted at an angle θ t given by: Liverpool City Council approved this expansion by using what are called delegated powers, meaning the plans did not come before the council's planning committee for a debate. Only 87 neighbouring homes were consulted about the expansion.

Special thanks to Andrew and Jeremy for doing a great job of providing a useful and captivating course that explained everything clearly. Also thanks to Shayz and Angela for organising and helping everything run smoothly, and everyone at Nottingham Trent University for their support and providing a great service.

In-situ SE uses light to probe the thin film in a noninvasive manner. The ellipsometer is outside the process chamber and light is allowed to enter through windows and interact with the sample. The light beam directly measures surface of interest without any damage or need for special sample preparation. Accurate: The same occurs at each interface where a portion of light reflects and the remainder transmits at the refracted angle. The boundary conditions provide different solutions for electric fields parallel and perpendicular to the sample surface. Therefore, light can be separated into orthogonal components with relation to the plane of incidence. Electric fields parallel and perpendicular to the plane of incidence are considered p- and s- polarised, respectively. These two components are independent and can be calculated separately. Fresnel described the amount of light reflected and transmitted at an interface between materials:

The group's formation - joining other local action groups like ARCH and Garston Futures - has been specifically inspired by a number of recent plans for the area focussed around heavy industry and the processing of chemicals and waste. Garston residents Patricial Putterill and Edna Dillon have both been sat listening intently throughout the meeting at the Woodcutters, with their sense of indignation rising with as each speaker lays out just how badly they feel this community has been treated. In November 2018, the Liverpool ECHO ran a story, with a headline that said developers wanted to transform Liverpool's 'forgotten suburb' with a huge new multi-million pound housing project.

About the Speakers

Spectroscopic ellipsometry (SE) and Spectrophotometry (R/T) are both optical measurement techniques. While spectroscopic ellipsometry measures change in polarization, R/T measures intensity of reflected or transmitted light. The techniques are often complementary and can be combined to provide more information about absorbing thin films (Hilfiker et al.). Synchronous operation of both compensators allows highly accurate data without waiting to “zone-average” over optical elements. Collect the entire spectrum (over 1000 wavelengths) simultaneously in a fraction of a second. Advanced “Dual” Light Source