▎ 摘　　要

NOVELTY - The FET has a substrate whose surface is provided with a suspended high conductivity micron or nano-wire material as a gate. An outer layer of the gate is orderly provided with a medium layer and a gas sensitive layer. Two ends of the gas sensitive layer and an end of the gate are deposited with a metal electrode for connecting an external test circuit. The metal electrode is provided with a first metal electrode and a second metal electrode. The first metal electrode and the second metal electrode are connected with the external test circuit. The substrate is made of silicon nitride, silicon oxide and polymer materials. The gas sensitive layer is made of metal oxide, heterojunction material and two- dimensional (2D) material and organic material, where the metal oxide is zinc oxide, tin oxide or iron oxide, the heterojunction material is p-n heterojunction and n-n heterojunction or Schottky junction. The 2D material is molybdenum disulfide or graphene. USE - Full-surrounding channel FET for use in a gas sensor. ADVANTAGE - The transistor has wide application range, and improves gas sensitivity of the gas sensor. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: (1) a full-surrounding channel FET manufacturing method; and (2) a full-surrounding channel FET utilizing method. DESCRIPTION OF DRAWING(S) - The drawing shows an front view of a full-surrounding channel FET.