Scientific Instruments Dresden (ScIDre) was founded in 2009 as a spin-off from the Leibniz Institute for Solid State and Materials Research Dresden (IFW Dresden). The unique floating zone crystal growth furnace HKZ, which was originally developed at IFW Dresden to operate under high gas pressures, was transferred as one of the first products to the emerging company. Since then, ScIDre optimized the plant design, completely reworked the control system and has sold the apparatus successfully world-wide. Based on the experience in engineering of high pressure and high temperature devices, ScIDre is continuously developing new, innovative instruments for the preparation and execution of crystal growth and other scientific experiments from various areas of solid state and materials research.
The abbreviation HKZ (Hochdruck-Kristallzüchtungsanlage) stands for a unique high-pressure optical floating zone crystal growth furnace. It features a vertical 2-mirror setup with a highly homogeneous and controllable light power distribution on the crystal rod. One of the key characteristics of the furnace is the ability to work at pressures of up to 150 bar with different gases and mixtures in the growth chamber. Additionally, individual gas flow rates can be adjusted and controlled freely and independently over the complete pressure range.
Using powerful xenon short arc lamps, melting temperatures over 3000 °C can be achieved. While the light power tuning range of arc lamps is limited, the thermal energy in the growth chamber is step-less adjustable between 0 and 100%, thanks to a power shutter system in the light beam. Highly precise, magnetically coupled linear and rotation feed through systems with pulling rates starting from 0.1 mm/h, advanced process monitoring technologies, and a comfortable PLC user interface guarantee extensive control of the growth process. The temperature of feed rod, melt zone and crystal is measured directly via a patented in-situ temperature measurement system. An optional after-heater is applicable with all possible atmospheres and pressures—also with high-pressure oxygen atmospheres.
Some material states with highly interesting properties are only stable under high temperatures and high pressure atmospheres with a precisely defined partial pressure of oxygen. During cooling and releasing the pressure to ambient conditions or changing the oxygen content in the atmosphere, these elusive states often decompose, making the analysis of their physical properties almost impossible. By quenching the sample within milliseconds under defined high pressure atmospheres, the metastable material states freeze and their properties remain under ambient conditions.
With the "Quenching and Gas Management Upgrade" to our High Pressure Oxygen Furnace we create an instrument, which combines the possibility to rapidly quench the sample, treat the sample under high temperatures, enable high gas pressures, and have full control of oxygen content in the process atmosphere between 0 and 100%.
The A-HSO is set up to operate vertically. The sample is mounted in a hanging position within the heating zone of the process chamber. When the sample is ready to be quenched, the mounting system is released and the sample drops into a quenching chamber, which is located underneath. The release of the sample mounting system and the drop of the sample can be triggered manually or automatically (e.g., after a certain amount of time or other measured value thresholds). The lower chamber is filled with the same atmosphere as the process chamber and is valved off with a rapidly operating automatic gate valve. During the process, the atmosphere around the sample can be freely adjusted in terms of total pressure, gas mixture and individual gas flow rates. The elaborated gas management system includes precise mass flow controllers for each gas and allows in-situ manual or automatic changes to the process atmosphere at any time during the process. A precise thermocouple element sits near the sample and a set of additional thermocouples monitors the furnace temperature in different places. All experimental parameters such as furnace and sample temperatures, gas pressure, mixture and flow as well as the release of the sample mounting system are controlled by a build-in computer.
The high-pressure multi-gas sintering furnace HMO allows heat treatment of materials under different atmospheres and enhanced pressures. It covers the range from sintering rods for crystal growth to maintaining phases which are only stable at higher pressures. Furnace can be used to retreat materials after crystal growth at high pressures up to 150 bar and at temperatures up to 1000°C.
The furnace is equipped with a special alloy tube offering an inner diameter of 15 mm and a heating zone of 200 mm with a low temperature deviation. The furnace setup with separated process and heating chambers allows the usage of almost any aggressive media and guarantees a long life span of the heating elements.
Scientific Instruments Dresden Furnace Data Sheet