Rapid Thermal Oxidation (RTO)
Rapid Thermal Oxidation (RTO) is a process used in semiconductor manufacturing to grow a thin oxide layer on silicon wafers using high temperatures (typically 900–1200°C) for short periods (a few seconds to minutes).
Key Features of RTO
- Fast Heating and Cooling:
- Heating rates of 50–200°C per second
- Cooling rates can be similarly rapid, preventing unwanted diffusion.
- Thin Oxide Growth:
- Typically 5–50 nm thick (much thinner than conventional furnace oxidation).
- Used for gate oxides, passivation layers, and surface preparation in MOSFETs and other devices.
Advantages of RTO
- Higher Throughput: Shorter oxidation times compared to traditional furnace oxidation.
- Better Uniformity: Localized rapid heating reduces thermal gradients.
- Reduced Contamination: Less exposure to ambient contaminants due to shorter processing time.
- Low Thermal Budget: Helps prevent excessive diffusion of dopants.
Comparison: RTO vs. Conventional Thermal Oxidation
| Feature |
RTO |
Furnace Oxidation |
| Temperature |
900–1200°C |
800–1100°C |
| Process Time |
Seconds to minutes |
Minutes to hours |
| Oxide Thickness |
5–50 nm |
20–1000 nm |
Would RTO Work for Your Application?
If you need ultra-thin, high-quality oxides for electrical insulation, fast processing to prevent diffusion in nanoscale devices, or high-uniformity coatings in MEMS/NEMS applications, RTO is a great choice.