Nuclear Spin‐Free ⁷⁰ Ge/ ²⁸ Si ⁷⁰ Ge Quantum Well Heterostructures Grown on Industrial SiGe‐Buffered Wafers

ABSTRACT The coherence of hole spin qubits in germanium planar heterostructures is limited by the hyperfine coupling to the nuclear spin bath due to and isotopes. Thus, removing these nuclear spin‐full isotopes is essential to extend the hyperfine‐limited coherence times needed to implement robust quantum processors. This work demonstrates the epitaxial growth of device‐grade nuclear spin‐free / heterostructures on industrial SiGe buffers while minimizing the amounts of highly purified and used. The obtained / heterostructures exhibit a dislocation density of and an isotopic purity exceeding , with carbon and oxygen impurities below the detection sensitivity, as revealed by atom probe tomography. Magneto‐transport measurements on gated Hall bars demonstrate effective gate control of hole density in nuclear spin‐free quantum wells. Negative threshold gate voltages confirm the absence of intentional doping in the wells, while Hall and Shubnikov–de Haas analyses yield consistent carrier densities () and high mobilities (). Mobility trends reveal interface‐trap‐limited scattering and percolation concentration below . These analyses, along with atomic‐level studies, confirm the high quality of epitaxial / heterostructures and their relevance as a platform for long‐coherence spin qubits.