Micropelt Papers
New high density micro structured thermogenerators for stand alone sensor systems (ICT 2007)
H. Böttner, J. Nurnus1), A. Schubert1), F. Volkert1)
Fraunhofer Institute for Physical Measurement Techniques (Fraunhofer IPM), Freiburg, Germany
1)Micropelt GmbH, Emmy-Noether-Str. 2, DE-79110 Freiburg, Germany
Abstract
Thermoelectric thin film micro-devices with high packing densities of thermoelectric legs are of high demand in microsystems for self-standing and so called waste energy selfpowered sensor systems for wireless data transfer. One technical solution for such micro-devices is offered by the Micropelt technology.
Formation of Nanometerscale Layers of V–VI (Bi2Te3-related) Compounds Based on Amorphous Prestages (ICT 2004)
H. Böttner, A. Schubert1), H. Kölbel, A. Gavrikov, A. Mahlke, J. Nurnus
Fraunhofer Institut Physikalische Messtechnik (IPM),
Heidenhofstr.8,
DE-79110 Freiburg, Germany
1)Infineon Technologies AG, Balanstr. 73, DE-81541 München, Germany
Micropelt® Miniaturised Thermoelectric Devices: Small Size, High Cooling Power Densities, Short Response Time (ICT 2005)
H. Böttner
Fraunhofer Institute for Physical Measurement Techniques (Fraunhofer IPM), Freiburg, Germany
Abstract
Thermoelectric thin film micro-devices, especially high cooling power density Peltier coolers, are in high demand for e.g. chip hot spot cooling, life science applications, HVAC (heating, ventilation and air-conditioning), telecommunication purposes or self standing and powered sensor systems. Obviously, such applications stand for industrial high volume quantities of reliable products. Thus a manufacturing process is required, which uses technologies similar to processes typically used in the production of microelectronics. The above mentioned key drivers for emerging markets are clearly applications around ambient temperature. Since their discovery in the 1950, bismuth telluride (V–VI) related compounds have been favoured. Based on this, the Micropelt concept for thermoelectric devices with thin film thermoelectric layers in common vertical architecture on silicon substrates were successfully invented and developed.
Here, we will summarise the technological steps and present the state-of-the-art of the development of those Micropelt devices. The properties of Micropelt devices including their material properties, cooling performance and response time will be reported. Results of a new method for chemical gas analysis in the field of laser spectroscopy, which depends on the fast response time of Micropelt devices, will be shown.
Formation of Nanometerscale Layers of V–VI (Bi2Te3-related) Compounds Based on Amorphous Prestages (ICT 2004)
H. Böttner, A. Schubert1), H. Kölbel, A. Gavrikov, A. Mahlke, J. Nurnus
Fraunhofer Institut Physikalische Messtechnik (IPM),
Heidenhofstr.8,
DE-79110 Freiburg, Germany
1)Infineon Technologies AG, Balanstr. 73, DE-81541 München, Germany
Abstract
Superlattices (SLs) based on thermoelectric (TE) compounds would be able to outperform normal TE-materials. This is in particular important for the main TE materials that are V–VI related compounds and applications around room temperature. Due to the required nanometer scale of the individual SL-layers, questions concerning their structural stability may arise. To minimise interdiffusion during growth, the superlattices are deposited at ambient temperature and then annealed. In this report we will present studies concerning the growth, stability and crystallisation of n-type V–VI-compounds and SLs deposited at ambient temperature. The layers are structurally characterised using XRD-, SIMS- and SEM-analysis. In addition, we will report on the resulting thermoelectric properties.
Micropelt®: State Of The Art, Road Map and Applications (ETS 2004)
H. Böttner1), J. Nurnus1), M. Braun1), J. Wöllenstein1), F. Volkert2), A. Schubert2)
1)Fraunhofer Institut Physikalische Messtechnik (Fraunhofer IPM),
Freiburg, Germany
2)Infineon Technologies AG, München, Germany
Abstract
Here we present the state-of-the-art and the roadmap of Micropelt devices. The properties of Micropelt devices, in particular their fast response times, offer new possibilities e.g. for laser tuning, gas sensors and humidity sensing. Results of applications utilising Micropelt Peltier coolers will be presented.
New Thermoelectric Components using Microsystem Technologies
H. Böttner1), A. Schubert2), K.H. Schlereth3), D. Eberhard1), A. Gavrikov1), M. Jägle1), G. Kühner1), C. Künzel1), J. Nurnus1), G. Plescher1)
1)Fraunhofer Institut Physikalische Messtechnik (Fraunhofer IPM),
Freiburg, Germany
2)Infineon Technologies AG, München, Germany
3)Osram Opto Semiconductors, Regensburg, Germany
Abstract
This paper describes the first thermoelectric devices based on the V–VI-compounds Bi2Te3 and (Bi Sb)2Te3 which can be manufactured by means of regular thin film technology in combination with microsystem technology. The production concept, material deposition for some 10µm thick layers and the properties of the deposited thermoelectric materials will be described. First device properties for Peltier coolers and thermogenerators will be shown as well as investigations on long-term and cyclic stability. Data on metal/semiconductor contact resistance were extracted from device data. Device characteristics like response time for a Peltier cooler and power output for a thermogenerator will be compared to commercial devices …
Thermoelectric Micro Devices: Current State, Recent Developments and Future Aspects for Technological Progress and Applications (ICT 2002)
H. Böttner
Fraunhofer Institute for Physical Measurement Techniques (Fraunhofer IPM), Freiburg, Germany
Abstract
… worldwide efforts are undertaken to expand the technology for thermoelectric devices into the field of typical microsystem technologies, including aspects of advanced low dimensional high ZT materials. Until now, favourite material systems have been the bismuthtelluride (V–VI) compounds and the silicon/germanium (IV–IV) alloys. Recent results document that low dimensional material of both material systems can be integrated into microsystem devices, and demonstrate the suitability of wafer-based microelectronic technologies for the manufacturing of thermoelectric devices – even for the non-CMOS bismuthtelluride related compounds. This this survey will present the state of the art in a summary of recent results together with a more extensive description of the Micropelt approach as an example for a wafer based manufacturing concept close to microelectronics manufacturing …
Thin film based thermoelectric energy conversion systems (ICT 2002)
J. Nurnus1), H. Böttner1), C. Künzel1), U. Vetter1), A. Lambrecht1), J. Schumann2), F. Völklein3)
1)Fraunhofer Institut Physikalische Messtechnik (Fraunhofer IPM), Freiburg, Germany
2)Leibniz-Institut fuer Festkoerper- und Werkstofforschung (IFW), Dresden, Germany
3)Fachhochschule Wiesbaden (FHW), FB Physikalische Technik, Ruesselsheim, Germany
Abstract
Until now, thermoelectric materials used in commercial energy conversion devices like infrared sensors, Peltier coolers or thermogenerators have not taken advantage of the enormous potentials provided by low-dimensional structures. This paper presents the experimental verification of the predicted increase of the thermoelectric figure of merit (FOM) ZT in low-dimensional systems above values of bulk materials. Concepts for the realisation of devices using low-dimensional structures based on classical thermoelectric materials (V–VI-compounds for temperatures around 300 K and IV–VI-materials for temperatures up to 600 K, silicides for high-temperature applications) were made …
