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
Wearable cameras is next boom market for image sensors
April 17, 2015
Annual shipments of wearable cameras will surpass 30 million units by 2020 according to market research firm Tractica.
Paper memory ready to roll
Acuity Brands targets precise indoor positioning sector
Automotive chip reliability: a matter of design methods
Could Electrolyte Genome accelerate search for battery winners?
2.1A LDO+ regulator with cable drop compensation
April 16, 2015
This video explores the LT3086, a new member of our LDO+ family. It provides many functions in addition to regulation. It ...
Newswatch: ARM seeks energy harvesting edge in IoT push
GPTG agrees global distribution deal with Digi-Key
ST's Crolles strike rumbles on
- Smart Capacitive Design Tips
- Wireless MCUs and IoT
- Battery Management System Tutorial
- Deciding if Automated Test is right for your Company
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, DecaWave is offering EETimes Europe's readers the chance to win two TREK1000 kits to evaluate its Ultra-Wideband (UWB) indoor location and communication DW1000 chip in different real-time location system topologies.
Worth €947, the kit allow designers to prove a concept within hours and have a prototype ready in days. Based on the two-way ranging scheme, the kit lets you test...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.