| 摘要 |
PROBLEM TO BE SOLVED: To attain a small pressure sensor which has high accuracy even under an environment of high temperature. SOLUTION: A cavity R between diaphragms (semiconductor crystal layers 103, 104) and a sapphire substrate 101 is formed by the transverse growing action of the semiconductor crystal layer 103. In the diaphragm of two-layer structure, a channel (face-like collector of negative polarized pole) composed of a highly concentrated two-dimensional electronic gas is formed on a hetrojunction interface by a piezoelectricity peculiar to a nitride semiconductor. Since the stress applied to the heterojunction also changes if the external pressure to the diaphragm changes, the electric conductivity (sheet resistance) of the channel also changes sensitively. As the result, the external pressure of the diaphragm can be measured by reading the amount of variation of its resistance value because the resistance between two ohmic electrodes (source electrode 107S and drain electrode 107D) changes correspondent to the external pressure. COPYRIGHT: (C)2007,JPO&INPIT
|
