Capacitive gas sensor and preparation method

• Main Authors: KANG XIAOXU, ZHONG XIAOLAN
• Format: Patent
• Language: Chinese; English
• Published: 16.06.2020
• Subjects: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIRCHEMICAL OR PHYSICAL PROPERTIES; MEASURING; PHYSICS; TESTING

The invention discloses a capacitive gas sensor. The capacitive gas sensor comprises a shielding layer, support columns, interdigital electrodes located above the support columns and a sensitive layerfilled between the interdigital electrodes, wherein the shielding layer is located below and around the gas sensor; when gas diffuses to the upper surface of the gas sensor, chemical or physical reaction occurs between the shielding layer and the sensitive layer, so capacitance between the interdigital electrodes is changed. According to the capacitive gas sensor and the preparation method provided by the invention, the influence of an electric field between the interdigital electrodes on an external circuit can be shielded, and the sensitivity of the sensor is remarkably improved by changingthe height of the sensitive layer and increasing an air gap between the supporting columns. 本发明公开的一种电容式气体传感器，包括屏蔽层、支撑柱、位于支撑柱上方的叉指电极以及填充在叉指电极之间的敏感层；所述屏蔽层位于气体传感器的下方和四周，当气体扩散至气体传感器上表面时，与所述敏感层发生化学或物理反应，从而使得叉指电极之间的电容发生变化。本发明提供的一种电