Heat treatment is able to cause the structure transformation of phthalocyanine thin film either during the gas sensing operation or during the post-deposition heat treatment. The annealing effects of the two processes on the film characteristics and sensing properties of vacuum deposited copper phthalocyanine thin films were studied. The results show that the structure re-organization of CuPc film occurs during the sensing period when the sensing is operated at temperature up above 225 °C. Such structure transformation was inhibited by post-deposition annealing at 300 °C. However, the pre-annealing leads to a larger-grain and a more compact structure. As a result, the film sensitivity and response rate of sensing experiment are decreased after the heat treatment due to the reducing in the surface area. On the contrary, the recovery characteristic of the CuPc film is improved after heat treatment.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Surfaces and Interfaces
- Surfaces, Coatings and Films
- Metals and Alloys
- Materials Chemistry