Intel's FinFETs are less fin and more triangle
May 21, 2012 // Peter Clarke
Reverse engineering and analysis consultancy Chipworks Inc., has posted microscope cross-sections of parts of the 22-nm Ivy Bridge processor from Intel that has revealed that the FinFETs, which Intel calls tri-gate transistors, are in fact trapezoidal, almost triangular, in cross-section.
The ICs were 64-bit, four-core Xeon E3-1230 CPUs intended for the server market, which Chipworks (Ottawa, Ontario) said it obtained in Hong Kong, China.
The triangular section is markedly different to the idealized rectangular section that Intel had shown previously in 2011. However, it is not clear whether the non-vertical sides to the fins are a non-critical manufacturing artifact or are deliberately engineered by Intel and have a critical impact on electron mobility or yield.
Gold Standard Simulations Ltd., (Glasgow, Scotland), a spin-off from the University of Glasgow led by Professor Ase Asenov as CEO, responded by saying on its website: "There is a lot of speculation about the possible advantages and disadvantages of the trapezoidal, or almost triangular, shaped 'bulk' FinFET." GSS has performed a simulation analysis of the FinFET using its statistical 3-D TCAD simulator called Garand.
GSS's simulation was used to explore the dependence of threshold voltage on gate length for the trapezoidal Intel transistor and an equivalent rectangular-fin transistor. "Clearly the rectangular fin has better short channel effects. Still, the million-dollar question is if the almost-triangular shape is on-purpose design, or is this what bulk FinFET technology can achieve in terms of the fin etching?"
The comparisons between dimensionally comparable rectangular and trapezoidal FinFETs are not markedly different but as GSS had no knowledge of doping profiles it assumed a lightly doped channel. At the same time GSS acknowledged that there is a high doping concentration stopper below the fin in the shallow trench isolation (STI) region. "Clearly FinFETs are more complicated devices in terms of understanding and visualization compared to the old bulk MOSFETs," GSS concluded.
Dick James' blog at Chipworks
GSS' discussion of trapezoidal FinFET All news
Never lose track of things
March 30, 2015
This month, DecaWave is offering EETimes Europe's readers the chance to win two TREK1000 kits to evaluate its Ultra-Wideband ...
Graphene's first commercial success: energy-saving light bulbs?
Nanolaser enables on-chip photonics
New cyber-physical systems as the basis for IoT: Europe has it all
1.5-A LDO plus regulator monitors current and temperature
Sensor data predict failure of large machines
March 29, 2015
Long before they actually fail, large machines exhibit signs of wear and tear. A team of researchers from the Saarland University ...
Big data sets drones to fly
CE marking misconceptions
Fraunhofer launches test centre for high-voltage batteries
- Intelligent Over Temperature Protection for LED Lighting Applications
- Intel helps to Turbocharge Infotainment Systems Designs
- High Performance Portable DC Bench Power Supply: Save Money and Free Up Bench Real Estate by Building Your Own
- Software-Defined Radio Handbook
InterviewInfineon: CAN FD success goes at the expense of FlexRay
The faster version of the venerable CAN bus, CAN FD is currently taking off at several carmakers. Infineon's Thomas Böhm, Head of Body / Automotive, believes this could well go at the expense of FlexRay. ...
Filter WizardCheck out the Filter Wizard Series of articles by Filter Guru Kendall Castor-Perry which provide invaluable practical Analog Design guidelines.
Linear video channel
READER OFFERRead more
This month, Freescale is giving away 5 RIoTboards, worth 74 dollars each, for EETimes Europe's readers to win.
Designed to run Android operating systems efficiently or to run under Linux, the board is based on the Freescale i.MX 6Solo processor; using the ARM Cortex-A9 architecture.
The RIoTboard platform also includes a rich set of peripherals including a 10M/100M/Gb Ethernet port, 1...MORE INFO AND LAST MONTH' WINNERS...
December 15, 2011 | Texas instruments | 222901974
Unique Ser/Des technology supports encrypted video and audio content with full duplex bi-directional control channel over a single wire interface.