• wall zpolar cubic equation.png

A 2nm equivalent production fab with

 

No Steppers

 

-Foundation semiconductor building block 'reinvented'
-Security of Supply, security of IP and reduced spin time

This article provides a brief insight into VZTL which supersedes ZTL, the initial technology covered on this website, first published 2022.

What do exploding new markets including Electric Vehicles (EV), Artificial Intelligence (AI), Big Data, Cloud, Smart Homes, the IoT have in common? Answer: they are all made possible by the semiconductor industry. It's been the same for a little over 60 years as developments in integrated circuits (ICs) have created new industries with products such as the PC and the smart phone. By combining and shrinking many billions of circuit elements onto piece of a silicon wafer, computing machines can be created on a tiny device measuring just a few square millimeters. We have all heard that our smartphone is a more powerful computer than the one that sent Apollo 11 to the moon in 1969. That is due to this continual process of integration, which is commonly expressed as Moore's law, the observation by Intel's Gordon Moore that the number of transistors in an IC double about every two years.

Background
Transistors are the basic electronics building blocks, used to amplify or switch electrical signals and power. The first working device was demonstrated by William Shockley and colleagues in 1947. The first commercial transistor on silicon was a bipolar junction transistor (BJT) made by Texas Instruments. Then, in 1959, a new type of transistor was invented at Bell Labs by Mohamed Atalla and Dawon Kahng. The metal–oxide–semiconductor field-effect transistor (MOSFET), or MOS transistor, had the huge advantage that it could be miniaturized and mass-produced and it had a much lower power consumption and higher density than bipolar junction transistors, making it possible to build high-density ICs as discussed. In the 1980s, CMOS (complementary metal-oxide semiconductor) became the dominant transistor fabrication technology, and now, 99% of the world’s ICs - digital, analogue and mixed-signal - use MOS i.e., unipolar transistors.

Current Semiconductor Problems
But there is a problem. As ICs have grown to include billions of transistors capable of delivering advanced computers on a single chip, they have become increasingly complex to manufacture. Internally, transistor features and connections have been shrunk and shrunk, now measuring in single figure nanometres. For comparison, a human hair is 80,000- 100,000 nanometres (nm) in diameter. The most state-of-the-art CMOS processing technology has device features that measure just 3nm. Not only this, but ICs can have up to 100 layers, including circuits, connections and isolation. According to a Bloomberg article from May 2021, 'The Chip Shortage Keeps Getting Worse. Why Can’t We Just Make More?': "Manufacturing a chip typically takes more than three months and involves giant factories, dust-free rooms, multi-million-dollar machines, molten tin and lasers. The end goal is to transform wafers of silicon—an element extracted from plain sand—into a network of billions of tiny switches called transistors that form the basis of the circuitry that will eventually give a phone, computer, car, washing machine or satellite crucial capabilities."

New fabs (semiconductor manufacturing plants) with equipment that can produce these highly complex chips cost billions of dollars to build. That is why many companies (such as Qualcomm, AMD and Nvidia) opt for the 'fabless' model, having their ICs made for them by third parties such as the Taiwanese company, Taiwan Semiconductor Manufacturing Company (TSMC). The title of a Wall Street Journal article in June 2021, says it all: ' The World Relies on One Chip Maker in Taiwan, Leaving Everyone Vulnerable'. The article claims that TSMC makes "almost all of the world's sophisticated chips, and many of the simpler ones too". Another view, given by Dan Wang, a technology analyst at research firm Gavekal, is that TSMC "manufactures around 50% of all semiconductors in the world." (including) "some of the most advanced chips out there”. According to Wang: "only TSMC and Samsung have "foundries capable of manufacturing the most advanced 5-nanometer chips". The chips in your iPhone are made by TSMC.

Solution
What if...the basic semiconductor building block were re-invented?
Given this situation, what if a technology could be found that simplified the manufacture of ICs? What if device geometries did not have to be so small? What if the number of layers could be reduced? What if you could do this without a high-risk change in materials from silicon which is proven in the industry over many decades and in abundant supply? What if the fabs and equipment were readily available at quite ordinary facilities all around the world? What if devices could be made in just a few days rather than months. What if devices could be made with even greater performance at lower power?

What if? We're about to find out...
A technology enabler, SFN (Search for the Next) has invented, developed, patented, and now proved a new process and transistor technology, that slashes manufacturing time from 15 weeks to a several days, removes the need for steppers altogether and reduces the process steps from thousands to a few hundreds. These 'Bizen' transistors using a technology known to SFN as Zpolar are still made on standard silicon process technologies and can be produced in all fabs including those that pre-date steppers. Yet the devices themselves will have the same or better performance than the most advanced CMOS chips.

They are smaller, lower power and faster. To get technical, Bizen - a contraction of ‘Bipolar’ and ‘Zener’ - uses the Zener tunnel mechanism, a reverse voltage pre breakdown mechanism in which the high electric field generated at P-N junction causes electrons to tunnel from the valence band to conduction band of a semiconductor device. The Zener tunnel mechanism is well-known, but most previous work on Zener diodes has focused on the post reverse voltage breakdown effect for circuit regulation, protection and surge (high voltage) suppression.

Going back 60 years
SFN has gone back to the original BJT. Bizen’s development using physics has led to Zpolar as an alternative to both the bipolar (BJT) and unipolar (MOS). We have been able to develop a hair trigger logic with push-pull edges, from one of the key basic elements in semiconductor design."

Basic logic gates produced using Zpolar consist of a single transistor with multiple non-base-like inputs using tunnelling. To turn the input on or off, a tiny voltage is provided to the tunnel input with a tunnelled bi-directional output. This is unlike a normal device BJT acting in bipolar or MOS acting in unipolar. This has the comparative advantages of increased speed (only a small voltage needs to be switched in order to change the current output) and of smaller size. A two-input NOR gate produced comprises a single transistor with two tunnel like inputs. Higher input NOR gates can be made by adding more tunnel inputs to the transistor, but no further transistors are required reducing capacitance and area. We call this Bizen logic family, “Vertical Zpolar Tunnel Logic” (VZTL).

Many axes of opportunity
SFN has proven technology that provides an alternative to the process physics, process flow, transistor, logic and so all markets including automotive, consumer, telecoms, computing, medical, IoT, industrial etc. The scale of opportunity is exceptional.

The foundation physics has been changed with the Bizen wafer process using Zener tunnel mechanics which provides new devices on the wafer that use the Zener tunnelling mechanism within a new PDK (Process Development Kit). SFN has specifically invented the Zpolar to allow tunnel mechanics to replace resource heavy conventional electronics. This allows a change to the application circuits so a new standard cell library has been developed including the implementation of entire logic cells in a single transistor which allows VZTL. This results in change to finished products which may be processors or power devices. Bizen fabrication is fast and sufficiently low in cost to allow greater integration of the electronics market.

This reduction in manufacturing speed, simplicity and steppers without a costly and time-consuming change in technology allows an older fab or even a discrete level fab the ability to go onchip, and so increase the efficiency of infrastructure. Again, This this is a huge opportunity.

What stage is Bizen at?
SFN has made remarkable progress. In Q3 2021 the company finished characterising the Bizen wafer process and created a data book of 100s of different kinds of transistor element that are required to make an IC. These have been modelled in SPICE for use in a PDK (Product Development Kit) by Cadence, the world's leading IC design tools company. This means that IC makers can design and simulate using Bizen. These elements are being combined into logic functions, AND/OR/NOR gates, comparators, op amps and other functions commonly used in ICs.

SFN is providing the stepper free lithography and metrology required to enable existing fabs use Bizen to allow even a multi core AI style microprocessor to be mass produced without the need of a stepper of any geometry and with lower power consumption.

However, unlike conventionally produced parts, the Bizen technology parts can be made in just a few days (as opposed to months) on pretty much any fab in the world, helping security of supply.

Opportunities
SFN has redefined the transistor enabling devices to be made more quickly and with less complex machinery than is currently the case, reducing the financial and technical barriers to chip manufacturing. Steppers and neon gas are not required to achieve 2nm. Because the Bizen transistor design is much easier to implement than the CMOS design this technology provides a new lease of life for Fab’s running older generation semiconductor manufacturing equipment. These mature fabs are able to produce far more complex devices than at present and achieve much greater degrees of integration. Many circuit boards with discrete components will become just single devices. If we consider removing many of the passives, discretes and PCBs, we can envisage Bizen transistors providing opportunity in all electronics markets.

We are offering manufacturing franchises to companies who would like to take the manufacturing of their chips in-house. All the IP is proven and patented.

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SFNBizen

Process Of Reference

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The process of reference ‘POR’ defines the physics of the Bizen wafer process.

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SFNZpolar

Process Development Kit

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The process development kit, PDK, are the Bizen devices PDK including the Zpolar Transistor and tunnels.

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SFNZTL

Library Cells

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The Bizen cell libraries including the Zpolar Tunnel Logic (ZTL) family.