A quantum chip is like a layered cake: superconducting metal, a thin insulator layer, and more metal. Previously, layers were applied through a polymer mask, like a stencil for paint. The polymer left invisible droplets on the surface that degraded superconductivity and compromised cleanliness.

Now, the mask is gone. Instead, grooves are etched into the silicon, like furrows in a garden bed. Metal is deposited directly into these grooves, settling evenly without chemical residue. The method is compatible with standard chip fabrication: the same machines, the same technology.

Almost no contaminants were found at the metal-silicon interface. And the variation in qubit lifetime over 35 hours was narrow and steady, like a healthy person's pulse. This means the qubits behave predictably.

This approach expands the choice of materials and substrate cleaning methods. Quantum computers are getting closer to mass production, just like transistors once did.