EDITION 4
PHOTONICS Leveraging know-how in optics and semiconductor EXTRACTS FROM LAYERS 4
CHAPTER
PHOTONICS Photonics – Meet the Team Augmented reality – At the touch of a button! Scintillator Technology – Going digital!
4
LAYERS 4 | PHOTONICS | MEET THE TEAM
Dr. Heiko Plagwitz Product Marketing Manager Heiko gained his first degree in physics in Germany in 2002 before completing a PhD in 2007 specialising in Solar Technology. He continued to work in project management roles within the solar industry before joining Oerlikon in 2011 as a senior scientist. His focus is now functional coatings including AR, DLC and antismudge layers.
Photonics
PHOTONICS A CONVERGING WORLD OF OPTICS AND SEMICONDUCTOR Dr. Volker Wuestenhagen Head of BU Photonics Volker qualified as a physicist before completing his PhD in surface science in 1992. He gained his first professional experience of thin film technology in the optical disk industry in 1993 before joining Unaxis in 2003 where he held process development, R&D and business management roles. He was responsible for Evatec’s Inline systems business prior to becoming Head of BU Photonics.
PHOTONICS Filters Functional Coatings With our long experience in both optics and semiconductor, Evatec is well placed to solve the challenges and address the increasingly demanding requirements for process control and handling set by the photonics industry. This year’s LAYERS gives you just a taste of how wide a range of applications our knowhow supports.
Volker
Dr. Clau Maissen Senior Product Marketing Manager A physicist, Clau gained his PhD in 1992. He has over 30 years experience in the field of coatings and systems holding management positions in development and manufacturing for optical and solar applications. In March 2018 he became Senior Product Marketing Manager for Evatec’s Photonics Business Unit with particular focus on high performance filter technologies.
5
6
LAYERS 4 | PHOTONICS | AUGMENTED REALITY
AUGMENTED REALITY – AT THE TOUCH OF A BUTTON! The age of fully automated independent production is here using SOLARIS® inline sputter tools. Senior Product Manager Stephan Voser explains how SOLARIS® can easily handle a whole range of optical thin film processes for existing and upcoming applications such as Augmented Reality in a fully automated way at just the touch of a button.
Photonics
7
8
LAYERS 4 | PHOTONICS | AUGMENTED REALITY
CASE STUDY
Drift Control SOLARIS® configuration
Handling sequence
Cassettes holding 6 or 8 inch substrates are loaded by the operator at the front end and the recipe is selected. The operator presses “go” and the system does the rest - loading the carriers, loading to the system, unloading and finally loading all “good” coated substrates back to the original cassette.
PC3: SiO2 Layer 2b & 6b
Quality control (particles)
PC4: Nb2O5 Layer 3
PC5: SiO2 Layer 4 & 6c
PC2: SiO2 Layer 2a & 6a
Pick from cassette
Load to carriers
Load to system and coat and unload from system PC1: Nb2O5 Layer 1 & 5
PC6: SiO2 Layer 6d
Carrier unload
Quality control (particles and optical performance)
Process setup
Back to cassette
Deposition rates:
Optimised setup, 2 passes around the system:
Nb2O5: 5.5 nm/s
Thicker SiO2 layers split > cycle times: 11s + 11.5s
SiO2: 2.3 nm/s
Throughput: 150 carriers/hr
Photonics
AR Coating – sample runs It takes just a few minutes to complete the first sample runs until the system is in a steady state and coatings are well within specification. Continuous production can then begin.
9
10
LAYERS 4 | PHOTONICS | AUGMENTED REALITY
Keeping particles under control SOLARISÂŽ is designed to minimise particles at every step. Substrates are brought to the system in closed cassette environments, robot loading and unloading takes place in a closed environment under HEPA Filters and the system design itself is also optimised for particle reductionSputter deposition takes place in small process chambers with water cooled flanges to give the most stable
process conditions to reduce particle risk. Deposition control without the need for uniformity shapers using active cathode magnet control is another important risk reduction measure. For processes like the AR Coatings in this case study we can achieve less than 0.15 adders/cm2 between 0.4 and 10 Âľm
Photonics
Making production easy Apart from process control capabilities like “Drift Control” and particle monitoring, SOLARIS® uses well proven automation technology to ensure that the line runs flexibly and independently and with full production tracking. The system can be converted quickly between different substrate sizes, e.g. 150 or 200mm or for different layer thicknesses as the need arises. The handling system is adapted from the semiconductor industry with proven handling speeds and reliability that easily satisfy the demands needed for optical substrate processing. The production history for each and every substrate is individually tracked and checked, and the data logged for QA purposes. Any “defective” substrates entering or leaving the system are automatically segregated in buffer stations according to QA needs. Cassette to cassette handling means operator interaction is limited to simple loading and unloading of cassettes to and from the system with no manual substrate handling at all.
Taking integration one step further MES integration is available for fabs also wanting to integrate SOLARIS® with upstream and downstream processes. The image below shows just how such a set up works in practice where 8 SOLARIS® are integrated into a customer’s fab for production of smart devices.
11
12
LAYERS 4 | PHOTONICS | SCINTILLATOR TECHNOLOGY
Photonics
13
SCINTILLATOR TECHNOLOGY GOING DIGITAL! Evaporation solves the challenges for “thick� layer deposition to enable the latest large area digital scintillator technology for medical and industrial use. Evatec Product Manager Kurt Flisch tells us how.
FPD - A growing market in healthcare Digital X-ray detectors used in Flat Panel Detectors (FPDs) convert X-rays into electronic data that a computer can process and convert to an image quickly. These FPDs first convert X-rays into visible light through a scintillating medium and this visible light is then converted into electrical charge by a photodiode or TFT. The most common digital scintillators are based on materials like Caesium Iodide (CsI) and Thallium Iodide (TlI). FPD based systems are increasingly replacing the traditional analog and computed radiography (CR) systems used by the healthcare industry until now which have disadvantages of relatively high radiation exposure, poor image quality, long diagnosis time and the need for chemical processing. Some analysts expect that the FPD market in this sector will reach USD 1,700 Million dollars by 2021.
X-ray Object
Figure 1: Scintillator Function
Scintillator Visible light Detector Digital output Reflector Csl Scintillator
Figure 2: Structure
(source: www.abyzr.com/open_content/product/scintillator.php)
TFT panel Epoxy (glass) layer
14
LAYERS 4 | PHOTONICS | SCINTILLATOR TECHNOLOGY
Controlled rates for CsI and TlI during the entire deposition of 7 hours
Evaporation solves the manufacturing challenges for CsI/TlI Deposition of the layers required for the x-ray detector sets some interesting challenges to be solved The typical layers required are thalium doped CsI with typical doping rates of TlI of between 0.2% and 3.0%. A whole variety of panel sizes and shapes must be handled: square, rectangular up to a typical maximum of 17” x 17” (chest x-rays). The layer thicknesses required are much higher than in typical thin film deposition processes at 500 – 600 µm, and over 700 µm for moving image detectors. The typical substrate temperature must be kept below 150ºC during the whole deposition time of 5 or more hours. CsI and TlI exhibit unique non linear temperature gradation making control of source temperature during both ramp-up (shutter closed) and evaporation essential to maintain source stability during an extended process time. Accurate rate control of both materials during the entire evaporation process is also essential as scintillator performance is highly sensitive to small changes in TlI doping level.
Layer uniformity and doping levels must both be maintained across the large active substrate areas but uniformity shapers should be avoided by using a planetary tooling system to keep deposition rates high and maximise material material useage from the the large barrel sources required for such thick layers. Maintaining overall process stability and keeping substrate temperatures under control for extended process times is also a must. On a practical level system uptime and throughput needs to be maximised by optimising pumping performance and simplifying shield changes and cleaning procedures.
Dedicated sources and process control are key Evatec already has 10 years of experience in delivering dedicated scintillator systems. Custom evaporation sources, in-situ control of temperature rates during the entire process, as well as real-time process supervision and data logging are just a few of the features which are essential for successful scintillator manufacture.
Photonics
Typical Evatec BAK1401 production tool for Scintillator
A growing market The high quality scintillators produced by evaporation today are mainly used in x-ray detectors for medical devices – portable or heavy-static – such as dental and mammography but there are other growth opportunities too. Analog x-ray detection can also be replaced with its digital counterpart in areas like nondestructive material inspection, human and/or luggage screening and Evatec’s BAK Evaporation system are ready.
15
www.evatecnet.com