This week, Silicon Valley-based Atomera announced it had entered a joint development agreement (JDA) with an unnamed “leading semiconductor provider.” Arguably the most significant part of the agreement was that it includes a manufacturing license allowing the unnamed provider to fabricate semiconductors that incorporate Atomera’s Mears Silicon Technology (MST).
In this article, we’ll take a look at what exactly MST is and why Atomera thinks it can extend Moore’s law.
Mears Silicon Technology
Developed in 2001, Mears Silicon Technology is Atomera’s materials science technique for producing semiconductors, which yield some significant improvements over conventional silicon.
Standard vs. MST transistors. Image used courtesy of Atomera
MST works on an atomic level to insert very thin layers of a non-semiconductor, like oxygen, into the semiconductor material. The introduction of this new oxygen barrier helps to increase the concentration of dopants in the semiconductor. By increasing the concentration of the dopants, the flow of current through a transistor is forced into a more directed path.
The result is transistors with a higher electron-mobility since carriers will avoid collisions with the crystalline structure of the semiconductor. MST is said to improve the performance of the transistor with respect to diffusion blocking, mobility, gate leakage, and reliability.
Benefits of MST
One benefit of MST is that it offers unique diffusion blocking properties. Atomera says the introduction of MST significantly inhibits the ability of dopants to diffuse via oxidation-enhanced diffusion.
Dopant concentration vs depth showing the unique doping profiles available via MST. Image used courtesy of Atomera
The result is that designers can create unique doping profiles that offer performance benefits. For example, dopant concentration can be lowered by the gate electrode in order to improve mobility.
As previously mentioned, the more directed path created by MST increases carrier mobility. This, along with the mobility benefits from dopant concentrations, doubly improves the mobility of carriers in MST devices. The result is transistors with faster switching speeds, more current for the same voltages, and fewer subthreshold gate leakages.
Finally, Atomera claims that MST can benefit reliability specs such as the time to dielectric breakdown (TDDB), the charge to dielectric breakdown (QBD), and PMOS negative bias temperature instability (NBTI).
A Creative Extension of Moore’s Law?
Because of the techniques used in MST, Atomera has claimed to find a way to improve transistor performance without following the worn-out path of downscaling. This becomes important as Moore’s Law is coming to a halt, and designers continue to think outside the box to improve device performance.
Atomera asserts that MST is complementary to other nano-scaling technologies and can be implemented on standard manufacturing tools without significant overheads. By joining up with a leading provider in the semiconductor industry, Atomera has indicated that its technology is ready for market, and will start being integrated in products designers may recognize in the coming years.