Nav: Home

Reducing down to one-third of thermal resistance by WOW technology for 3-D DRAM application

April 24, 2017

Researcher team led by Professor Takayuki Ohba at Tokyo Institute of Technology, ICE Cube Center, in collaboration with the WOW (Wafer-on-Wafer) Alliance(term 2), an Industry-academic collaborative research organization consisting of multiple semiconductor related companies aiming for practical applications of 3D IC technology, demonstrated the thermal resistance of the 3D stacked device can be reduced down to less than 1/3 relative to the conventional one bonded by bump(term 3) 3D IC in Through-Silicon-Via (TSV) wiring(term 4). Since semiconductor circuits are highly heat-generating bodies during operation, when heat is hard to be released, the temperature of the semiconductor results in highly rise, which leads to be a malfunction. The development of heat dissipation technology has been a big challenge.

To address this challenge, Ohba and colleagues analyzed thermal properties in 3D IC using finite element method (FEM)(Term 5) and thermal network calculation method. The study identified three main factors of thermal resistance; the interconnection layers, dielectric layers and organic layers in the conventional bump type device. Contrary to the bump type, the thermal performance of a bumpless 3D IC was almost 150 times better than that of a conventional IC at the same TSV density. The researchers demonstrated to reduce the total thermal resistance to 0.46 Kcm2/W, whereas the conventional method is 1.54 Kcm2/W. This suggests that the bumpless enables lower temperature rise and three to four times further DRAM stacking.

Based on their demonstration experiments, the scientists will work toward practical use of large-capacity memory technology for mobile terminals and servers.
-end-
The results of this research were reported at the International Conference of Electrics Packaging 2017 (ICEP2017) held in Tendo, Japan on April 19-21.

Explanations of Technical Terms

1 WOW 3D technology: 3D integration technology for making large-scale integrated circuits by wafer stack (Wafer-on-Wafer). There is stack methods including Chip-on-Chip (COC) and Chip-on-Wafer (COW) and productivity increased in the order of COC < COW < WOW.

2 WOW Alliance: A research group conducting at the Tokyo Institute of Technology and cooperated with semiconductor-related companies including design, process, device, materials, and research institutions. It succeeded in the world's first development of the bumpless TSV 3D technology, enabling wafer stack easily even thinned-down wafers.

3 Bumps: Joint metal material formed by electroplating method.

4 TSV wiring: Through-Silicon-Via wiring. A connection hole that penetrates the silicon wafer and connects the upper and lower chips with embedded wiring.

5 FEM: Finite element method. A kind of numerical analysis method called finite element method.

Tokyo Institute of Technology

Related Technology Articles:

April's SLAS Technology is now available
April's Edition of SLAS Technology Features Cover Article, 'CURATE.AI: Optimizing Personalized Medicine with Artificial Intelligence'.
Technology in higher education: learning with it instead of from it
Technology has shifted the way that professors teach students in higher education.
Post-lithium technology
Next-generation batteries will probably see the replacement of lithium ions by more abundant and environmentally benign alkali metal or multivalent ions.
Rethinking the role of technology in the classroom
Introducing tablets and laptops to the classroom has certain educational virtues, according to Annahita Ball, an assistant professor in the University at Buffalo School of Social Work, but her research suggests that tech has its limitations as well.
The science and technology of FAST
The Five hundred-meter Aperture Spherical radio Telescope (FAST), located in a radio quiet zone, with the targets (e.g., radio pulsars and neutron stars, galactic and extragalactic 21-cm HI emission).
AI technology could help protect water supplies
Progress on new artificial intelligence (AI) technology could make monitoring at water treatment plants cheaper and easier and help safeguard public health.
Transformative technology
UC Davis neuroscientists have developed fluorescence sensors that are opening a new era for the optical recording of dopamine activity in the living brain.
Do the elderly want technology to help them take their medication?
Over 65s say they would find technology to help them take their medications helpful, but need the technology to be familiar, accessible and easy to use, according to research by Queen Mary University of London and University of Cambridge.
Technology detecting RNase activity
A KAIST research team of Professor Hyun Gyu Park at Department of Chemical and Biomolecular Engineering developed a new technology to detect the activity of RNase H, a RNA degrading enzyme.
Taking technology to the next level
Physicists from the ARC Centre of Excellence for Ultrahigh bandwidth Devices for Optical Systems (CUDOS) developed a new hybrid integrated platform, promising to be a more advanced alternative to conventional integrated circuits.
More Technology News and Technology Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Clint Smith
The killing of George Floyd by a police officer has sparked massive protests nationwide. This hour, writer and scholar Clint Smith reflects on this moment, through conversation, letters, and poetry.
Now Playing: Science for the People

#562 Superbug to Bedside
By now we're all good and scared about antibiotic resistance, one of the many things coming to get us all. But there's good news, sort of. News antibiotics are coming out! How do they get tested? What does that kind of a trial look like and how does it happen? Host Bethany Brookeshire talks with Matt McCarthy, author of "Superbugs: The Race to Stop an Epidemic", about the ins and outs of testing a new antibiotic in the hospital.
Now Playing: Radiolab

Dispatch 6: Strange Times
Covid has disrupted the most basic routines of our days and nights. But in the middle of a conversation about how to fight the virus, we find a place impervious to the stalled plans and frenetic demands of the outside world. It's a very different kind of front line, where urgent work means moving slow, and time is marked out in tiny pre-planned steps. Then, on a walk through the woods, we consider how the tempo of our lives affects our minds and discover how the beats of biology shape our bodies. This episode was produced with help from Molly Webster and Tracie Hunte. Support Radiolab today at Radiolab.org/donate.