A layer of diamond can prevent high-power electronic devices from overheating.
Powerful electronic components can get very hot. When many components are combined into a single semiconductor chip, heating can become a real problem. An overheating electronic component wastes energy and is at risk of behaving unpredictably or failing altogether. Consequently, thermal management is a vital design consideration.
This becomes particularly important in devices made from gallium nitride. “Gallium nitride is capable of handling high voltages, and can enable higher power capability and very large bandwidth,” says Yong Han from the Singapore's Agency for Science, Technology and Research (A*STAR) Institute of Microelectronics. “But in a gallium nitride transistor chip, the heat concentrates on tiny areas, forming several hotspots.” This exacerbates the heating problem.
Han and co-workers demonstrate both experimentally and numerically that a layer of diamond can spread heat and improve the thermal performance of gallium nitride devices.
The researchers created a thermal test chip that contained eight tiny hotspots, each 0.45 by 0.3 millimeters in size, to generate the heat created in actual devices. They bonded this chip to a layer of high quality diamond fabricated using a technique called chemical vapor deposition. The diamond heat spreader and test chip were connected using a thermal compression bonding process. This was then connected to a microcooler, a device consisting of a series of micrometer-wide channels and a micro-jet impingement array. Water impinges on the heat source wall, and then passes through the micro-channels to remove the heat and keep the structure cool.
Han and the team tried their device by generating 10–120 Watts of heating power in test chips of 100 and 200-micrometer thickness. To dissipate the heating power, the diamond heat spreading layer and microcooler helped maintain the structure at a temperature below 160 degrees Celsius. In fact, the maximum chip temperature was 27.3 per cent lower than another device using copper as the heat spreading layer, and over 40 per cent lower than in a device with no spreading layer.
The experimental results were further confirmed by thermal simulations. The simulations also indicated that the performance could be improved further by increasing the thickness of the diamond layer, and that good bonding quality between the gallium nitride chip and the diamond heat spreader was crucial to obtain the best performance.
“We next hope to develop a novel micro-fluid cooler of higher and more uniform cooling capability, and to achieve thermal management using a diamond layer of high thermal conductivity near an electronic gate,” says Han.
The A*STAR-affiliated researchers contributing to this research are from the Institute of Microelectronics
Han, Y. Lau, B. L., Tang, G. & Zhang, X. Thermal management of hotspots using diamond heat spreader on Si microcooler for GaN devices. IEEE Transactions on Components, Packaging and Manufacturing Technology 5, 1740–1746 (2015).
A*STAR Research | Research SEA
Researchers use light to remotely control curvature of plastics
23.03.2017 | North Carolina State University
TU Graz researchers show that enzyme function inhibits battery ageing
21.03.2017 | Technische Universität Graz
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
24.03.2017 | Materials Sciences
24.03.2017 | Physics and Astronomy
24.03.2017 | Physics and Astronomy