A SiCN Thin Film Thermistor Based on DVB Modified Polymer-Derived Ceramics

Area of Science:

• Materials Science
• Ceramic Engineering
• Sensor Technology

Background:

• Developing advanced materials for reliable temperature sensing in the medium-low range (30-400 °C) is crucial.
• Polysilazane (PSN2)-derived silicon carbon (SiCN) ceramics offer potential but often require property enhancement for specific applications.
• Achieving high electrical conductivity and suitable microstructure in SiCN thin films remains a challenge.

Purpose of the Study:

• To prepare carbon-rich SiCN ceramics using divinylbenzene (DVB)-modified polysilazane (PSN2).
• To fabricate a high-conductivity SiCN thin film sensor for medium-low temperature sensing.
• To investigate the effect of DVB modification on the electrical conductivity, microstructure, and temperature resistance of SiCN ceramics.

Main Methods:

• Synthesis of DVB-modified PSN2 liquid precursors.
• Patterning of SiCN resistive grids using direct ink writing (DIW).
• Characterization of electrical conductivity, microstructure, and oxidation resistance of the fabricated SiCN ceramics.
• Measurement of temperature resistance performance in the range of 30-400 °C.

Main Results:

• DVB modification significantly increased the critical thickness of SiCN ceramics.
• The electrical conductivity of SiCN was substantially improved by DVB incorporation, meeting sensing requirements.
• SiCN ceramics with low DVB content demonstrated excellent electrical conductivity and good oxidation resistance.
• The DVB-modified SiCN resistance grids showed suitable performance in the 30-400 °C temperature range.

Conclusions:

• DVB modification is an effective strategy to enhance the properties of PSN2-derived SiCN ceramics.
• The developed DVB-modified SiCN thin film sensors are suitable for medium-low temperature sensing applications.
• The improved conductivity and oxidation resistance of these SiCN ceramics open avenues for advanced sensor development.