By Zvi Or-Bach, Contributor
The upcoming IEEE S3S Conference 2015 in Sonoma, CA, on October 5-8, will focus on key technologies for the IoT era. It is now accepted that the needs for the emerging IoT market are different from those that drive the high-volume PC and smart-phone market. The Gartner slide below illustrates this industry bifurcation where traditional mass products follow the ever more expensive scaling curve, while IoT devices, with their focus on cost, power, flexibility and accessibility, will seek a place near its minimum.
The current high-volume market is focused on a few foundries and SoC vendors driving a handful of designs at extremely high development cost each, processed at the most advanced nodes, with minimal processing options. In contrast, the emerging IoT market is looking for older nodes with lower development costs and a broad range of process options, and has many more players both at the foundry side and the design side.
The key enabling technologies for the IoT market are extremely low power as enabled by SOI and sub-threshold design, integrated with multiple sensor and communication technologies that are both enabled by 3D integration. All of these combine in forming the IEEE S3S unified conference.
This year’s conference includes many exciting papers and invited talks. It starts with three plenary talks:
- Gary Patton – CTO of Global Foundries: New Game Changing Product Applications Enabled by SOI
- Geoffrey Yeap – VP at Qualcomm.: The Past and Future of Extreme Low Power (xLP) SoC Transistor, embedded memory and backend technology
- Tsu-Jae King Liu – Chair of EE Division, Berkeley University: Sustaining the Silicon Revolution: From 3-D Transistors to 3-D Integration
The following forecast from BI Intelligence suggest that the semiconductor technologies that are a good fit for the future market of IoT should be of prime interest for the semiconductors professional.
Jim Walker, Research VP at Gartner, argued at the “Foundry vs. SATS: The Battle for 3D Wafer Level Supremacy” market symposium that 3D ICs are the key enabler of performance and small form factor of products required for IoT.
The upcoming IEEE S3S conference provides an important opportunity to catch up and learn about these technologies.
Let me share with you some nuggets from the monolithic 3D integration part of the conference:
Prof. Joachin Burghartz of the Institute for Microelectronics Stuttgart will deliver an invited talk on “Ultra‐thin Chips for Flexible Electronics and 3D ICs” which will present a process technology to fabricate flexible devices 6-20 microns thin. This process flow is currently in manufacturing in their Stuttgart fab, as depicted below:
Another interesting discussion will be presented by NASA scientist Dr. Jin-Woo Han who will describe “Vacuum as New Element of Transistor”. These transistors are made of “nothing” and could be constructed within the metal stack, forming monolithic 3D integration with silicon-based fabric underneath.
In his invited talk “Emerging 3DVLSI: Opportunities and Challenges” Dr. Yang Du will share Qualcomm’s views on monolithic 3D IC, which they term 3DVLSI and illustrate below, which seems very fitting for IoT applications.
Globalfoundries will present joint work with Georgia Tech on “Power, Performance, and Cost Comparisons of Monolithic 3D ICs and TSV-based 3D ICs”. This work again shows that monolithic 3D can provide a compelling alternative to dimensional scaling as illustrated by the following chart.
Monolithic 3D will present “Modified ELTRAN (R) - A Game Changer for Monolithic 3D” that shows a practical flow for existing fabs to process monolithic 3D devices using their exiting transistor process and equipment. This flow leverages the work done by Canon about 20 years back called ELTRAN, for Epitaxial Layer Transfer. The following slide illustrates the original ELTRAN flow.
By deploying the elements of this proven process, a multilayer device could be built first by processing a multilayer transistors fabric at the front end of line, and then process the metal stacks from both top and bottom sides.
The conference includes many more interesting invited talks and papers covering the full spectrum of IoT enabling technologies. In addition, the conference offers short courses on SOI application and monolithic 3D integration, and a fundamental class on low voltage logic.
New technologies are an important part of the future of semiconductor industry, and a conference like the S3S would be a golden opportunity to step away for a moment from the silicon valley, and learn about non-silicon and silicon options that promise to shape the future.