Instead of conventional 1-or-0 computer bits stored in the form of electrical charges, quantum information is stored and manipulated in the form of quantum bits (qubits), which can have multiple values simultaneously. One highly promising qubit candidate is a single atom of elements such as phosphorus (P) buried in ultra-pure silicon-28.
These atoms can be precisely placed using a scanning tunneling microscope (STM).
Instead of searching 40,000,000 square micrometer [4mm x 10 mm] surface area for a one square micrometer area – patterns pinpoint the spot
Using an STM for qubit fabrication requires making electrical connections to the P qubits and wire-like deposits less than 1/100th the width of a human hair. Until now, that has generally been possible only by using disparate, complicated and expensive instruments, the cost of which can easily exceed $10 million, and using onerous, one-off alignment procedures to coordinate the different steps and locate the qubits.