Piezo-Driven Uniaxial Strain Cell with Integrated RF for Si/SiGe Quantum Dots

Mechanical strain is a versatile control parameter for band structure, spin–orbit coupling, and valley physics in semiconductor spin qubits, but most piezoelectric uniaxial strain cells are optimized for bulk, high-aspect-ratio samples. We report a compact, piezo-driven uniaxial strain cell tailored to die-scale, square-profile chips typical of gate-defined Si/SiGe quantum-dot devices. The architecture seats a chip-level RF interposer directly above the actuators to co-integrate high-density DC and microwave routing with in-situ, continuously tunable strain at cryogenic temperatures. On this platform we mount Si/SiGe spin-qubit devices (Tunnel Falls) and measure strain transfer and device response at dilution-refrigerator temperatures, including Coulomb-blockade spectroscopy and magnetospectroscopy to probe charging energies and valley splitting as a function of applied strain.