There experience is hard-earned and well worth reviewing in our estimation. Below are listed some of their specuialties and links to them.

Preventive Maintenance

Critical Vessel Monitoring

Infrared Temperature Measurements Improve the Operation of Kilns M67 / M77 for kilnsTemperature Measurement

Cement_Sinter_Zone Overview of the Sinter Zone System

Window Selection

SpyGlass Viewports(408 KB) AppNote# spyglassviewports.pdf

Substation Monitoring (927 KB) App Note#

New Role for Infrared in T&D: 24/7 Maintenance/ Security Monitoring of Substations
Critical Vessel Monitoring (301 KB) App Note # criticalvessel.pdf

Blackbody Calibration Sources Function as Standards Blackbody Standards (830 KB) App Note #BB Calibration of Infrared Instruments.

Lens Cleaning General Maintenance of IR Lenses(680 KB) TechNote #2

Furnace Exit Temperature Monitoring Using Non-Contact Infrared Sensors.

Furnace Temperature Monitoring in the Power Industry M67 for CO2 measurement(225 KB)

Aluminum MeasurementMI-S12AL for Aluminum measurement(883 KB) AluminumBrochure Measurement of Aluminum temperature.

Infrared Temperature Measurements of Plastic and other Organic Films M67 for thin plastic films (504 KB) App Note #11Temperature Measurement of Plastic Film.

Continuous Monitoring of Web Temperature in Industrial Dryers M67 for web temperature (327 KB) App Note #12

Notes for Gypsum Industry Hardening Processes MikroLine 212814.pdf IR-Line camera for the control of hardening processes in the gypsum industry.

Mineral & Glass Wool Production Notes MikroLine 2128IR-line camera for the quality control during production of mineral and glass wool.

MikroLine 2128

The rationale for using a thermal infrared approach in semiconductor wafer processing is explained at the outset of their note, as follows:

During epitaxial growth the wafer temperature is one of the key parameters. It influences
such elements as growth rate, composition of ternary and quaternary compounds and doping
levels. Wafer temperature also has an important impact on the quality of the grown layer and
its roughness and thereby on the performance of devices based on such epitaxial layers. Thus,careful monitoring and precise control of wafer temperature during the whole growth process are indispensable. Usually the temperature is controlled indirectly, either by thermocouples or by pyrometers.

The article goes on to describe how their pyrometry (radiation thermometry) method obtains the true temperature.

In brief, their technique works as follows:

Reflection of the thermal radiation at interfaces (of semiconductor layers) leads to interference and thus to an intensity modulation (of thermally emitted radiation), depending on the layer thickness in the pyrometry measurement. True wafer temperature is given by a correction according to an additional measurement of reflectance at the same wavelength (using a seperate source of illumination).

You can read the details by downloading the PDF file at the Laytec GmbH website or by downloading it from their website by clicking here.

The study was performed on two identical Gallium Nitride (GaN) buffer growth runs monitoring the effect of the Sapphire substrate backside polishing on the true temperature signal using the Laytec IR Pyrometer. The only difference in the growth parameter was the substrate type: wafer #1 was a sapphire 2” wafer with a rough backside, and wafer #2 a double side polished 2”sapphire wafer.

To quote one interesting comment:

“The effect of the double side polished sapphire on the reflectance signal is a certain increase in the average reflectance (the back side reflectance contribution) and a relative shrinking of the Fabry-Perot oscillation amplitude. All these effects could be perfectly modelled by the LayTec’s AnalysR
software”

You can view the complete Applications note, TT measurements: double side polished vs. single side polished sapphire substrates, or download it from the Laytec website by clicking here (PDF - 122 Kb).

pdf - 122 kb

The lead in to the applications note reads as follows:

“LayTec’s in-situ sensors are state-of-the-art in-situ growth monitors for basic growth studies, process development, process transfer and for enhancing run-to-run reproducibility in production environment. These sensors are offered for a variety of growth systems in MBE, MOVCD and other growth techniques. All sensors are available with LayTec ?s True Temperature measurement mode based on emissivity corrected pyrometry: EpiTT, EpiR TT and EpiRAS TT“.

You can download a copy of the entire note: “True wafer temperature measurements in MBE “- CLICK HERE - PDF - 122 Kb

Thermoforming Applications: Thermoforming Temperature Measurement

The Thermoforming Application

Thermoforming is the process of using heating elements and/or cooling elements to mold or shape
some type of material. Typically this material will be a type of plastic.

The process follows a path from extrusion to molding. Most thermoforming companies will use extrusion machines to extrude the plastic, which then will be pulled into an oven and heated until it reaches a certain temperature.

Once this temperature has been obtained the plastic is moved out of the oven into a cooling and molding zone. Usually the machine runs on a timer so the temperature of the plastic varies and is inconsistent within the oven.

The plastic is molded and cooled either by water-cooling or air-cooling. Most applications use water-cooling either sprayed onto the plastic or pushed through the metal mold.

Finally, the plastic is moved to a cutting zone where the shapes are cut out of the plastic. This can be done either manually or automatically as well.

This application has a couple of different sections that are ideal for infrared pyrometers and imaging.

The first area that pyrometers or imaging is appropriate for occurs after the plastic has been extruded as a sheet and before it goes into the oven. In this area the plastic is warm coming out of the oven and has no ability for a thermocouple to be mounted at any point.

Knowing the temperature at this point will allow the operator to slow down the process if the temperature is too warm or quicken the process if the temperature is too cool. Here there is no cover to the plastic that would block the field of sight, therefore imaging or single point pyrometers are appropriate solutions.

The other potential reason to image or gauge temperature at this point is due to the fact that the
temperature variations here can affect the quality of the final molded plastic product.

This was said to be an issue at a certain thermoforming plant where they used an infrared gun to get the temperature at a single point, and they created statistics on the temperature versus quality. However, this is not proven to be an imperative measurement due to the fact that there are many variables that can attribute to temperature changes further down in the process.

Still it is strongly recommended to consider this point of measurement because this temperature still has some affect on the total process. Imaging will allow for an entire profile of the plastic, and allow for possible adjustment of the extrusion die heads if there are areas of the plastic that are warmer than others.

The purpose is to hopefully create a consistent sheet of plastic. On the next page is a picture of a Polystyrene sheet of extruded plastic before it goes into the thermoforming oven: