Mathematical modeling of response dynamics of n-type SnO2-based thick film gas sensor
Materials Science in Semiconductor Processing, cilt.190, 2025 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 190
- Basım Tarihi: 2025
- Doi Numarası: 10.1016/j.mssp.2025.109360
- Dergi Adı: Materials Science in Semiconductor Processing
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, PASCAL, Applied Science & Technology Source, Chemical Abstracts Core, Chimica, Communication Abstracts, Compendex, Computer & Applied Sciences, INSPEC, Metadex
- Anahtar Kelimeler: CO, Ionized oxygen, Modeling, Semiconductor gas sensor, Tin oxide
- Orta Doğu Teknik Üniversitesi Adresli: Evet
Özet
The sensing mechanism of semiconductor metal oxide (SMOX) gas sensors has a complex nature due to the physical and chemical phenomena involved. In this study, a comprehensive transient mathematical model was developed considering mass transfer, detailed surface reactions, electron transfer, and DC electric current flow between electrodes. The model was tested for the response of n-type SnO2 thick film sensors to CO gas in a dry-air environment. The results provide critical insights into the effects of crucial parameters like operating temperature, film thickness, and pore size on the two main competing mechanisms: the relative rates of surface reduction/oxidation and the rates of diffusion and surface reaction of CO. The simulation results were compared with the experimental response profiles of 7 μm thick SnO2 film for three different step pulses of magnitudes of 400 ppm, 800 ppm, and 1500 ppm CO concentrations under a continuous flow of dry air at T = 528K.