Product Demonstration, Webinar
Inside PsiQuantum: The Photonics Chip Never Seen Before
- Technology and Substrate Alignment
- The facility utilizes Molecular Beam Epitaxy (MBE) to fabricate films on 300mm wafers, aligning directly with the standard 300mm silicon technology platform used by major global foundries.
- The specific material grown is Barium Titanate (BTO), layered atop a Strontium Titanate (STO) film, which sits on a bulk crystalline silicon substrate.
- The resulting film thickness ranges from a few nanometers to a few hundred nanometers, requiring high-precision control over the ratio of the three constituent elements (Strontium, Barium, Titanium).
- Process Mechanisms and Environmental Controls
- MBE operates in an ultra-high vacuum environment with pressures reaching $10^{-10}$ to facilitate evaporation of metallic precursors from heated crucibles onto the wafer.
- Chamber walls are cooled to -10°C to ensure evaporated metals condense immediately upon contact rather than bouncing back and contaminating the film.
- A separate -50°C coolant system circulates through internal tubes to manage thermal dynamics within the reaction chamber.
- Film growth requires a slow deposition rate to maintain crystalline structural integrity and minimize defects, as rapid growth compromises the crystal lattice.
- The facility operates within a Class 1,000 cleanroom (and adjacent Class 100 areas) to prevent airborne particle contamination, a requirement mandated for eventual integration into silicon semiconductor production lines.
- Personnel utilize full-body bunny suits and protective gear to handle heavy metal precursors and prevent contamination of the BTO-STO films.
- Material Handling and Safety
- Precursors (strontium, barium, titanium metals) are stored in sealed containers; the chamber is only opened for refilling, ensuring no exposure to air.
- Materials are shipped to partners like GlobalFoundries immediately after the BTO layer is grown to ensure integration into high-volume manufacturing lines.
- Automated transfer systems move wafers from the MBE machine directly into sealed boxes, eliminating manual handling to prevent defects.
- Safety protocols include full mask protection and specialized procedures for handling heavy metal elements and managing potential surface oxidation risks.
- Quality Assurance and Characterization
- Post-fabrication testing includes high-vacuum sealing and heating to observe material behavior and verify quality before component deployment.
- RHEED (Reflection High-Energy Electron Diffraction) is used to analyze lattice structures, where the resulting diffraction patterns (Kikuchi lines) confirm crystalline quality.
- Visual inspection of wafers relies on optical interference; specific colors indicate film thickness uniformity, as varying thicknesses alter the wavelength of reflected light.
- Defective wafers are identified through color inconsistencies or interference patterns that deviate from expected optical properties.
- Strategic and Future Outlook
- The project targets the development of single-photon quantum computer components, where performance is strictly dependent on the precise composition and crystal structure of the BTO-STO films.
- The team is currently transitioning from a single-vendor supply chain to engaging multiple US-based vendors to support future production scaling.
- The automated, high-vacuum synthesis process is designed specifically for scalability into high-volume manufacturing environments.
- Current research includes exploring the dual utility of these wafers as potential storage vectors or qubits within quantum architectures.