Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Making 3-D Chips a Reality

01.09.2003


Rensselaer Researchers Pioneer Interconnect Technology that May Take Chips Into 3-D



Researchers led by Ronald J. Gutmann in the Focus Center-New York at Rensselaer (FC-NY-RPI) are pioneering new interconnect technologies that promise to deliver smaller, faster, inexpensive, microelectronics and circuits that function in three dimensions.

Researchers at Rensselaer’s Focus Center-NY for Interconnections for Gigascale Integration believe that a strategy in which several chip wafers are bonded together in 3-D and interconnected provides an effective means to integrate chip technologies, and will dramatically improve performance and function. Working with collaborators from the semiconductor industry and other universities, the Rensselaer team is developing more effective interconnects that will allow information to get where it’s going more quickly and make computing ever faster.


Jian-Qiang “James” Lu, a research associate professor of physics and electrical engineering, presented some of their findings in a paper co-authored with International SEMATECH (Austin, Texas) at the International Interconnect Technology Conference (IITC) in June.

“At Rensselaer, we’re working with others to develop a very promising approach to building vertically integrated (3D) circuits; going up instead of across”, says Lu.

Vertical Bridges to the Next Level

An interconnect is essentially a vertical bridge to another level. But it’s nearly impossible to keep building such bridges in two dimensions, Lu explains, because bridges span a chip similar to the way the Brooklyn Bridge spans the East River.

“It’s a matter of necessity to consolidate space on a chip. Since real estate is dwindling as chip size decreases, the only way to go it seems, is up,” says Lu. “If you’re in a city, like New York for example, and you want to increase and expand the scale of your business, you need to increase real estate, narrow the streets, and build bridges. But New York City is only so big, so you need to build skyscrapers. It’s the same with chips, Rensselaer is attempting to build the information bridges for the chip skyscrapers.”

If you want the signal to travel from one side of the chip to the other, there will be a delay because the global circuit wire is so long in 2-D (typically travel is 10,000 microns). One simple solution to interconnectivity is to cut that large chip to several small chips, then stack and connect them vertically. By cutting and stacking interconnects you can slash that global travel distance to 10 microns or less (chip-to-chip).

Damascene Processing

To make and interconnect 3-D chips, Lu explains Rensselaer’s process of effectively bonding wafers together face-to-face. After bonding and thinning the top wafer, inter-wafer interconnects are formed using the industry standard “damascene” processing. This process includes drilling a hole using dry etching, filling it with copper (the industry standard material), and polishing away extra copper define the metal lines that will carry signals around the “stacked-chip” product. Gutmann was a leader in developing this damascene process for defining metal lines. This damascene interconnect formation process, combined with wafer alignment, bonding and thinning, can be repeated for the third wafer, says Lu.

"We’re developing monolithic wafer-level 3-D integration processes that potentially can achieve all the advantages of system-on-a-chip and system-in-a-package, while lowering cost, enabling the use of small form factors and achieving high performance," Lu said.

Hyper-Integration

Further advancements and benefits of such a system on a 3-D chip are that each layer can be optimized for any given technology, meaning in one 3-D chip you could integrate (hyper-integrate) terahertz technology, mixed signal processing, wireless and optical systems.

“Mixing the systems on a 3-D chip will enable technology for future chips to be low-cost and will also allow nanoelectronic, opto-electronic, and biochemical circuits to be integrated into heterogeneous systems,” says Lu. Several RPI faculty members lead design, modeling and applications-oriented efforts that support different aspects of this fairly large effort.

Also, the development cycles of various technologies using 3-D technology can be combined which compresses manufacturing time. Currently the cycles are dependant upon each other on a 2-D chip. With 3-D technology you can pick off-the-shelf technologies and plug them in, manipulating each layer separately and optimizing it to the needs of the user, explains Lu.

About Rensselaer’s Focus Center

The Focus Center-New York, Rensselaer is led by Timothy S. Cale, professor of chemical engineering, and is part of the Interconnect Focus Center (IFC): Interconnections for Gigascale Integration, that focuses on interconnects. The IFC is part of the SIA/DARPA driven Focus Center Research Program (FCRP), and focuses on the discovery and invention of new solutions that will enable the U.S. semiconductor industry to transcend known limits on interconnects that would otherwise decelerate or halt the rate of progress toward gigascale integration. The IFC officially started in October of 1998, and is headquartered at Georgia Institute of Technology. Other universities involved in the IFC, in addition to Rensselaer, include Massachusetts Institute of Technology, Stanford University, State University of New York at Albany, and the University of California, Los Angeles. The New York universities form the FC-NY, which is headquartered at SUNY Albany.

Technical Contacts: Tim Cale, Director, Focus Center-NY, Rensselaer:
Interconnections for Gigascale Integration
(518) 276-8676 or calet@rpi.edu
http://banyan.cie.rpi.edu/~cale/

James Lu, Research Associate Professor of Physics
(518) 276-2909 or luj@rpi.edu
http://www.rpi.edu/~luj


Theresa Bourgeois | Rensselaer News
Further information:
http://banyan.cie.rpi.edu/~cale/
http://www.rpi.edu/~luj

More articles from Information Technology:

nachricht Japanese researchers develop ultrathin, highly elastic skin display
19.02.2018 | University of Tokyo

nachricht Why bees soared and slime flopped as inspirations for systems engineering
19.02.2018 | Georgia Institute of Technology

All articles from Information Technology >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

Im Focus: Hybrid optics bring color imaging using ultrathin metalenses into focus

For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.

But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...

Im Focus: Stem cell divisions in the adult brain seen for the first time

Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.

The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...

Im Focus: Interference as a new method for cooling quantum devices

Theoretical physicists propose to use negative interference to control heat flow in quantum devices. Study published in Physical Review Letters

Quantum computer parts are sensitive and need to be cooled to very low temperatures. Their tiny size makes them particularly susceptible to a temperature...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

Researchers invent tiny, light-powered wires to modulate brain's electrical signals

21.02.2018 | Life Sciences

The “Holy Grail” of peptide chemistry: Making peptide active agents available orally

21.02.2018 | Life Sciences

Atomic structure of ultrasound material not what anyone expected

21.02.2018 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>