  The development of quantum annealing machines (QAMs) based on superconducting
qubits has progressed greatly in recent years and these machines are now widely
used in both academia and commerce. On the other hand, QAMs based on
semiconductor nanostructures such as quantum dots (QDs) appear to be still at
the initial elementary research stage because of difficulty in controlling the
interaction between qubits. In this paper, we review a QAM based on a
semiconductor nanostructures such as floating gates (FGs) or QDs from the
viewpoint of the integration of qubits. We theoretically propose the use of
conventional high-density memories such as NAND flash memories for the QAM
rather than the construction of a semiconductor qubit system from scratch. A
large qubit system will be obtainable as a natural extension of the
miniaturization of commercial-grade electronics, although further effort will
likely be required to achieve high-quality qubits.
