Monolithic integrable capacitive humidity sensing method for material characterization of dielectric thin films

• Published in: Microelectronics and reliability 2014-09, Vol.54 (9-10), p.1741-1744
• Main Authors: Rückerl, A., Huppmann, S., Zeisel, R., Katz, S.
• Format: Article
• Language: English
• Subjects: Applied sciences; Chemical vapor deposition (including plasma-enhanced cvd, mocvd, etc.); Cross-disciplinary physics: materials science; rheology; Design. Technologies. Operation analysis. Testing; Detection; Dielectric thinfilm; Dielectrics; Electronics; Exact sciences and technology; General equipment and techniques; Humidity; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Integrable humidity sensor; Integrated circuits; Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Microelectronic fabrication (materials and surfaces technology); Physics; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Semiconductors; Sensors; Sensors (chemical, optical, electrical, movement, gas, etc.); remote sensing; Silicon dioxide; Thin films; Vapour; Water vapour transmission rate; WVTR
• ISSN: 0026-2714; 1872-941X
• DOI: 10.1016/j.microrel.2014.07.038

A monolithic integrable capacitive humidity sensing method to determine water vapour transmission rates (WVTRs) of dielectric thin films is presented. The capacitive sensor, being used to detect transmission of water vapour, as well as the dielectric thin film to be tested can be processed subsequently with standard semiconductor technology. First measurements yield a reliable value of the well investigated dielectric silicon dioxide (SiO2). A 330nm thick plasma enhanced chemical vapour deposited film of SiO2 showed a WVTR of ∼1.6∗10-2±0.7∗10-2gm2∗d at 124°C and a step in surrounding relative humidity from 65% to 85%. The working principle of the sensor, its drawbacks and improvements are discussed and compared with other methods.