Reduce Dielectric Interfacial Defects to Improve Gate Oxide Properties
Studies show that reduction of interfacial defects leads to improved High k oxide properties. Memory and logic devices continue to shrink, pushing dielectric layers to the sub-nanometer range. Hydrogen peroxide gas enables in situ low temperature surface passivation that reduces dielectric layer defects.
Read "Anhydrous Hydrogen Peroxide Gas Delivery for Atomic Layer Deposition”.
Dielectric Layer Passivation and Functionalization
In situ gas phase surface passivation of SiGe channel materials can improve gate stack fabrication in logic devices. The passivation layer prevents atomic migration of channel materials into other layers. Passivation must leave the surface functionalized and ready for high k deposition. Passivation must not damage substrate.
Preparing for High K Deposition
Passivation layers must be ultra-thin so that they do not compromise high k properties. Typically 0.5 to 2 monolayers of passivation are desired. These layers must be uniformly deposited on three-dimensional structures such as FINFETs, MOSFETs and nanowire geometries.
Thin film deposition requires high conformality with nucleated growth in every unit cell. This high conformity ensures low defect density and low gate leakage. The biggest challenge is achieving a high quality interface between the substrate and the gate oxide.
Interfacial Defects and Dielectric Leakage
Interfacial defects and gate leakage lead to poor device performance, low yields, and reliability issues.
Detrimental surface features include:
- Dangling bonds on Ge and Si
- Ge-oxides with poor electrical properties
- Interlayer oxide defects that allow Ge migration into the High K dielectric
- Ge-Ge dimers
- High surface roughness
- Organic and carbon contamination
Reducing Defects using Hydrogen Peroxide Gas
Dry hydrogen peroxide gas can be used for in situ low temperature passivation. Studies show that this approach leads to fewer defects and better initiation layers for subsequent gate oxides.
RASIRC BRUTE Peroxide offers several unique benefits for surface passivation and surface functionlization of new channel materials:
- Functionalizes surface with –OH groups at temperatures as low as 25C
- Minimizes surface penetration and GeOx formation, due to its anhydrous properties
- Removes residual organic molecular contamination
Subsequent low temperature annealing at 300C removes remaining surface dangling bonds and surface roughness. A thermodynamically stable, thin, uniform, high quality interlayer dielectric results.
BRUTE Peroxide Beats Traditional Vaporizers and Passivation Technology
BRUTE Peroxide delivers up to 99.9% hydrogen peroxide particle-free gas by volume. No other commercial technology can deliver ultra-dry hydrogen peroxide gas.
BRUTE Peroxide is superior to other technologies for passivation and functionalization of new channel materials:
- Plasma technology requires line of sight not possible in high aspect ratio devices
- Ozone gas can burn and damage surfaces
- Bubblers deliver less than 1% hydrogen peroxide gas by volume
- Flash vaporizers create hydrogen peroxide droplets that lead to particle formation on surfaces
The new demands of next generation logic and memory devices make BRUTE Peroxide the best choice for reduction of interfacial defects and gate leakage.
Learn more about BRUTE Peroxide.
RASIRC products purify and deliver ultrapure gases from liquids. First to generate ultra-high purity steam from deionized water, RASIRC technology now also delivers hydrogen peroxide and hydrazine gases in controlled, repeatable concentrations. RASIRC gas delivery systems, humidifiers, closed loop humidification systems, and steam generators are critical for many applications in semiconductor, photovoltaic, pharmaceutical, medical, biological, fuel cell, and power industries. Applications include ALD, passivation, surface preparation, cleaning, sterilization, thermal oxidation, carbon removal and nitridation.