RASIRC BRUTE® Peroxide
Delivering Ultra-Dry Hydrogen Peroxide Gas
Next generation semiconductor materials and architectures require new precursors and oxidants for atomic layer deposition (ALD) and atomic layer etch (ALE) processes. H2O2 gas is a strong oxidant ideally suited for atomic level processes.
BRUTE Peroxide generates ultra-dry hydrogen peroxide gas and can be used with or without a carrier gas. Precursors that previously needed high temperatures or failed to grow uniform films with ozone, plasma, or water now have a new partner molecule for oxide film growth. BRUTE Peroxide is the only commercially available technology that can deliver up to 99.9% H2O2 gas by volume. Traditional H2O2 vaporizers, on the other hand, deliver less than 1% H2O2 gas by volume from standard H2O2 liquid source.
Advantages of H2O2 Gas for Next Generation Semiconductors
H2O2 gas can be the best choice when working with new materials and device architectures. Lower thermal budgets require a new oxidant that is more reactive than water yet less aggressive than either ozone or plasma. Silicon germanium and germanium react poorly to water and plasma. Technical studies have shown to uniform and stable passivation layers.
H2O2 gas delivered by BRUTE Peroxide creates a dense hydroxylated layer at a lower operating temperature than other oxidants. Tests show that high concentration H2O2 gas improves wafer coverage density over water by as much as three times. The result is better initial growth rates and fewer defects. BRUTE Peroxide enables process engineers to differentiate water from H2O2 in process reactions. It also avoids uniformity issues caused by water, and organic contamination in ozone that can result in high leakage current.
Innovative H2O2 Vaporizer Design
BRUTE Peroxide includes a vaporizer pre-loaded with a proprietary non-volatile solvent that ensures safety. The H2O2 liquid concentration is kept below 30% by weight. H2O2 diffuses across a proprietary membrane assembly, leaving the solvent behind. Once across the membrane, H2O2 is swept to process by a carrier gas or diffuses via vacuum conditions. H2O2 vapor pressure is 0.5 Torr at room temperature.
In contrast, vaporizers require high temperature to vaporize liquid droplets, leading to H2O2 decomposition and micro-droplet generation. Bubblers typically deliver less than 1% H2O2 gas by volume with the 99% balance water vapor due to Raoult’s Law. Both bubblers and vaporizers deliver high relative volumes of water along with H2O2 gas, reducing the oxidizing benefits of H2O2.
New Precursor for ALD
BRUTE Peroxide is ideal for next generation semiconductor materials and architectures that are adversely sensitive to higher temperatures and/or water vapor. When delivered ultra dry. H2O2 gas can directly react with metal precursors as water no longer interferes with reaction kinetics. On the other hand ozone not only reacts with the precursor but frequently with the layers below. Tests with hafnium and aluminum precursors show that H2O2 accelerates oxide growth. Nucleation density is improved 3x due to lower steric hindrance than water and ozone. In cleaning applications, high concentration H2O2 removes carbon from Germanium surfaces without causing damage.
Improving Atomic Layer Etch (ALE)
Anhydrous hydrogen peroxide gas provides the greatest flexibility to process engineers for advanced etching applications. Next generation processes require atomic-level etch precision; roughness must be minimized. Current ‘dry’ methods lack precision and selectivity for new materials like SiGe, Ge, and InGAs, and form volatile byproducts.
Better than Bubblers and Flash Vaporizers
BRUTE Peroxide sets a new standard for H2O2 delivery. Bubblers require carrier gas to bubble through liquid source H2O2. Bubblers cannot overcome Raoult’s Law so output is constantly changing. Temperature is typically higher than for RASIRC H2O2 vaporizers and bubblers always deliver water along with hydrogen peroxide.
Flash vaporizers require very high temperatures at or above boiling, which increases H2O2 decomposition and generates microdroplets. These devices also risk contamination and particles because they drip H2O2 onto a hot plate. Output from flash vaporizers tend to oscillate because of the difference between water and H2O2 boiling points and has an increased risk of downstream condensation. H2O2 gas output from flash vaporizers always includes water.
Versatility for Tight Process Control
With BRUTE Peroxide, process engineers can precisely control their processes. BRUTE Peroxide delivers hydrogen peroxide gas into a wide range of process conditions from vacuum to atmospheric pressure. H2O2 output ranges from 0.4 Torr to 6.7 Torr, depending on temperature. The maximum flow rate is 200 sccm.
More Information on BRUTE Peroxide
For more information about BRUTE Peroxide, fill out an information request form or contact RASIRC directly.