Light Reading
Infineon claims to have produced the first multilayer electronic integrated circuit -- a chip 'sandwich,' if you will

Infineon's Chip Sandwich

Light Reading
Out of the Lab
Light Reading
8/14/2002
50%
50%

Yesterday, Infineon Technologies AG (NYSE/Frankfurt: IFX) announced what it claims is a breakthrough in chip packaging technology: a technique that allows two electronic ICs (integrated circuits) to be squeezed into the space formerly occupied by one (see Infineon Intros 'Sandwich' Chip System).

Put simply, the German chipmaker has come up with a way to solder two chips together, one above the other, using a layer of copper in which chip-to-chip interconnections can be formed.

Infineon claims that its technology offers "a way out of the wiring crisis" -- referring to the fact that the number of pin-outs on a chip, and the number of traces on a printed circuit board, are starting to limit the functionality that can be put inside the chip itself. Reducing those wires to short copper links inside a "sandwich" allows chips to run faster, take up less space, and could reduce costs by up to 30 percent, the company contends.

Clever though it is, the idea of using stacked chips is not unique to Infineon. Others, including Sharp Foundry Services (part of Japanese electronics giant Sharp Ltd.) and Intel Corp. (Nasdaq: INTC), have developed so-called chip scale packages (CSPs) with up to four chips stacked on top of each other.

The different lies in the interconnects, says Reiner Schönrock, spokesperson at Infineon's worldwide headquarters in Munich. Stacked CSPs from other companies make connections using standard wire-bonding around the edges of the silicon die, rather than the copper sandwich developed by Infineon. "This [copper sandwich] is true 3D integration," Schönrock claims.

All stacked CSPs save on space and the costs associated with packaging, an approach that has turned out to be a big hit with manufacturers of mobile handsets. But Infineon's approach has several additional advantages over technologies from the likes of Sharp and Intel, which will open up other applications, says Schönrock.

For starters, the connections between chips are much shorter, so they can support faster speeds. The company claims that clock speeds of up to 200 GHz should be possible with its chips -- roughly 100 times faster than the fastest microprocessor today. This figure is a little hard to believe, but clearly this process has implications for fast communications technologies, including mobile and broadband networking.

The other key advantage is in heat dissipation. Since 80 percent of the chip's surface is covered by copper, which is a good conductor, the chip maintains an even temperature and can dissipate excess heat more easily. Furthermore, since the chip-to-chip interconnects are so short, they generate less heat in the first place than their wirebond counterparts.

The above image, taken with a microscope, shows how the chips are melded together. Infineon uses a diffusion soldering process, called SOLID, for "solid liquid interdiffusion."

First, a layer of copper is applied to the two surfaces to be bonded. Patterns are created in the copper using standard photolithography techniques to define where the interconnections will go. Then a thin layer (3 microns) of solder is applied, and the surfaces are pressed together at 3 bar of pressure and 270 degrees C, creating a permanent bond. The backsides of the two silicon wafers have been pre-polished, so that when they are bonded together, their combined thickness is almost the same as an original single slice of silicon.

In the image, places where current is flowing appear bright. Copper, which shows up pink, forms a channel from the top chip to the bottom chip. The grey areas at the top and bottom of the image are cross-sections of plain silicon -- the electronics are only found in the surface layer of the wafer.

Infineon's first prototype 3D IC, produced for an unnamed smart-card vendor, integrates a memory chip with the smart-card controller, increasing the available memory from the usual maximum of 32 kbytes to 160 kbytes.

Proving that it works is the first step, says Schönrock, and now the company will look at partnering with other chipmakers to produce products that meet their needs. There is also an obvious opportunity to apply this technique to products that Infineon makes itself, such as VDSL gear. The company also "hasn't ruled out the possibility" of licensing its technology to other foundries, he adds.

— Pauline Rigby, Senior Editor, Light Reading
http://www.lightreading.com Want to know more? The big cheeses of the optical networking industry will be discussing this very topic at Opticon 2002, Light Reading’s annual conference, being held in San Jose, California, August 19-22. Check it out at Opticon 2002.

Register now and save $500 off the registration fee. Just use the VIP Code C2PT1LHT on your registration form, and deduct $500 from the published conference fee. It's that simple!

(0)  | 
Comment  | 
Print  | 
Newest First  |  Oldest First  |  Threaded View
More Blogs from Out of the Lab
The US goverment has funded two projects to develop an optical packet router capable of scaling to 100 Tbit/s
BlazePhotonics has slashed losses in hollow fiber, according to research it presented at OFC
Intel's silicon modulator could turn out to be a bit of a letdown – because it's not all that fast
Xilinx is funding research that could lead to FPGAs replacing network processors in future optical networks
U. of Kansas researchers think they're close to multiwavelength all-optical clock recovery
Flash Poll
Wagner’s Ring
Data Centers Drive Telcos Into the Future

8|28|14   |   2:20   |   (2) comments


Data centers are at the heart of key trends driving telecom -- network virtualization, the drive for increased agility, and the need to compete with OTT providers.
LRTV Custom TV
Why SPs Should Consider Cisco's EPN

8|27|14   |   5:40   |   (0) comments


Sultan Dawood from Cisco discusses Cisco's EPN, which enables SPs to build agile and programmable networks delivering new network virtualized services using Cisco's Evolved Services Platform (ESP).
LRTV Huawei Video Resource Center
Huawei’s Showcase @ Big Telecom Event 2014

8|26|14   |   2.56   |   (0) comments


SoftCOM is Huawei's framework for telecom business and network transformation. Haofei Liu, Solution Marketing Manager, Carrier Business Group, Huawei, showcases Huawei's SoftCOM architecture in this video.
LRTV Huawei Video Resource Center
Huawei @ BTE 2014: Director of Integrated Solutions on SoftCOM & NFV Monetization

8|26|14   |   4.43   |   (0) comments


Libin Dai, Director of Integrated Solutions, Carrier Business Group, discusses Huawei's SoftCOM and NFV monetization. Huawei believes that NFV monetization should be service-driven rather than network-driven, and that operators should have network transformation, service transformation and a compatible and collaborative ecosystem in place in order to deploy NFV.
LRTV Huawei Video Resource Center
Huawei @ BTE 2014: Director of US NFV Lab on CloudEdge & the Future of NFV

8|26|14   |   4.06   |   (0) comments


Sean Chen, Director of US NFV Lab at Huawei, discusses Huawei's new approach to NFV in open collaboration. Huawei believes that through Proof of Concept tests, it could help operators learn and communicate with the industry more effectively. Sean believes that successful implementation of NFV should have its values reaching to end users and discusses how Huawei's ...
LRTV Huawei Video Resource Center
Huawei's Highlights @ Big Telecom Event 2014

8|26|14   |   3.34   |   (0) comments


At the Big Telecom Event in Chicago Huawei showcases its high-level strategy, the SoftCOM architecture, which helps operators reduce the cost of ownership of their network infrastructure and generate additional revenue in the ICT service environment. Huawei showcases over 30 pilot programs from across the globe, focusing on the industry-leading commercial ...
LRTV Custom TV
VeEX – Live from the Show

8|21|14   |   5:58   |   (0) comments


An overview of VeEX Test and Measurement solutions including TX300S multi-service test set with VeExpress cloud-based management system, UX400 universal modular platform supporting 100G testing, and the redesigned RXT modular platform.
LRTV Custom TV
Transitioning CE 2.0 Networks Into the SDN & NFV Era With Telco Systems

8|19|14   |   5:19   |   (0) comments


Telco Systems' Ariel Efrati (CEO) and Moshe Shimon (VP of Product Management) discuss virtualization and how the company's new Open Metro Edge solution utilizes the SDN and NFV concepts to accelerate and orchestrate service delivery through its innovative product portfolio and software applications.
LRTV Custom TV
NFV Myths: Is NFV Still Several Years Away?

8|11|14   |   1:13   |   (0) comments


Some say that NFV (network functions virtualization) is still several years away from being implemented on mobile operator networks. This isn't the case. Operators can get started on their paths to NFV now, as this short video from Skyfire shows.
LRTV Custom TV
A New Security Paradigm in SDN/NFV

7|28|14   |   02:54   |   (0) comments


Paul Shaneck, Global Director Network Solutions for Symantec, discusses the evolving virtualized network, explaining how Symantec is leading the security discussion as it relates to SDN and NFV, and helping to ensure the network is protected and compliant.
LRTV Documentaries
Sprint's Network Evolution

7|24|14   |   14:59   |   (0) comments


Sprint's Jay Bluhm gives a keynote speech at the Big Telecom Event (BTE) about Sprint's network and services evolution strategy, including Spark.
LRTV Documentaries
BTE Keynote: The Software-Defined Operator

7|24|14   |   18:43   |   (1) comment


Deutsche Telekom's Axel Clauberg explains the concept of the software-defined operator to the Big Telecom Event (BTE) crowd.
Upcoming Live Events!!
September 16, 2014, Santa Clara, CA
September 16, 2014, Santa Clara, CA
September 23, 2014, Denver, CO
October 29, 2014, New York City
November 6, 2014, Santa Clara
November 11, 2014, Atlanta, GA
December 9-10, 2014, Reykjavik, Iceland
June 9-10, 2015, Chicago, IL
Infographics
A survey conducted by Vasona Networks suggests that 72% of mobile users expect good performance all the time, and they'll blame the network operator when it's not up to par.
Hot Topics
Rogers, Shaw Take Aim at Netflix
Mari Silbey, Independent Technology Editor, 8/26/2014
Utilities to Pump $11.2B Into Smart Grid – Study
Jason Meyers, Senior Editor, Utility Communications/IoT, 8/26/2014
Verizon Launches QR Code Security Solution
Carol Wilson, Editor-at-large, 8/26/2014
Fiber Revival at Deutsche Telekom
Iain Morris, 8/25/2014
M2M's In Fashion: Wearables Play the US Open
Sarah Reedy, Senior Editor, 8/25/2014
Like Us on Facebook
Twitter Feed