Effect of Measurement System Configuration and Operating Conditions on 2D Material-Based Gas Sensor Sensitivity.

Gas sensors applied in real-time detection of toxic gas leakage, air pollution, and respiration patterns require a reliable test platform to evaluate their characteristics, such as sensitivity and detection limits. However, securing reliable characteristics of a gas sensor is difficult, owing to the structural difference between the gas sensor measurement platform and the difference in measurement methods. This study investigates the effect of measurement conditions and system configurations on the sensitivity of two-dimensional (2D) material-based gas sensors.

Thermal Decomposition In Situ Monitoring System of the Gas Phase Cyclopentadienyl Tris(dimethylamino) Zirconium (CpZr(NMe)) Based on FT-IR and QMS for Atomic Layer Deposition.

We developed a newly designed system based on in situ monitoring with Fourier transform infrared (FT-IR) spectroscopy and quadrupole mass spectrometry (QMS) for understanding decomposition mechanism and by-products of vaporized Cyclopentadienyl Tris(dimethylamino) Zirconium (CpZr(NMe)) during the move to process chamber at various temperatures because thermal decomposition products of unwanted precursors can affect process reliability. The FT-IR data show that the -CH peak intensity decreases while the -CH- and C=N peak intensities increase as the temperature is increased from 100 to 250 °C. This result is attributed to decomposition of the dimethylamido ligands.

Degradation Behaviors of NPB Molecules upon Prolonged Exposure to Various Thermal Stresses under High Vacuum below 10 Pa.

Understanding of the long-term thermal stabilities of organic light-emitting diode (OLED) materials during film deposition is important to accurately identifying their processing windows. The thermal stresses imposed on OLED materials in the evaporation source during the deposition process may cause phase transition and/or degradation of the source materials, which results in variations in their purity and thermal properties, such as the vapor pressure and, ultimately, the device degradation. In this work, we designed a simple and efficient apparatus to determine the long-term thermal stability of OLED materials, which allows prolonged heating of a minimal amount of the sample (∼2 g) for 50 h even under high vacuum below 10 Pa where the organic powder samples easily and rapidly vaporized because of exposure to temperature above their deposition temperature.