1. Hitachi Research Laboratory, Research & Development Group Hitachi Ltd. 7‐1‐1, Omika‐cho, Hitachi‐shi Ibaraki 319‐1292 Japan
2. Graduate School of Science and Engineering Ibaraki University 4‐12‐1, Nakanarusawa, Hitachi‐shi Ibaraki 316‐8511 Japan
3. Center for Technology Innovation – Electronics, Research & Development Group Hitachi Ltd. 1‐280, Higashi‐Koigakubo, Kokubunji‐shi Tokyo 185‐8601 Japan
4. Center for Technology Innovation – Material, Research & Development Group Hitachi Ltd. 7‐1‐1, Omika‐cho, Hitachi‐shi Ibaraki 319‐1292 Japan