TY - JOUR
T1 - Effects of substrate temperature on the film characteristics and gas-sensing properties of copper phthalocyanine films
AU - Lee, Yuh Lang
AU - Tsai, Wen Ching
AU - Maa, Jer Ru
N1 - Funding Information:
The support of this research by the National Science Council of the Republic of China through grant no. NSC 89-2214-E-041-002 is gratefully acknowledged. Professor Yu-Ming Yang is also acknowledged for his helpful discussions.
PY - 2001/3/29
Y1 - 2001/3/29
N2 - Copper phthalocyanine thin films were prepared by vacuum deposition at various substrate temperatures onto glass and gold. The effects of substrate temperature and material on film morphology and crystalline structure were studied, and the film characteristics were related to their gas-sensing properties for NO2. We find that CuPc films have fine-grain morphology and small degree of crystallization at low substrate temperature (Td = 28 °C). When Td is elevated to 100 °C, fiber-like morphology was observed on both substrates, with orientation mainly parallel to the substrate. At 150-200 °C, the fibers grow larger without significant change of orientation on glass, but whisker structures with less order were formed on gold. The fiber-like structure prepared at 100 °C has the highest electrical conductivity, which also implies that the stacking axis of the Pc macrocycle is the high conductivity direction. This characteristic also leads to quick response and higher sensitivity of this film to NO2. The effects of substrate temperature on the film characteristics and gas-sensing properties are compared to the heat-annealing effects observed in our previous work.
AB - Copper phthalocyanine thin films were prepared by vacuum deposition at various substrate temperatures onto glass and gold. The effects of substrate temperature and material on film morphology and crystalline structure were studied, and the film characteristics were related to their gas-sensing properties for NO2. We find that CuPc films have fine-grain morphology and small degree of crystallization at low substrate temperature (Td = 28 °C). When Td is elevated to 100 °C, fiber-like morphology was observed on both substrates, with orientation mainly parallel to the substrate. At 150-200 °C, the fibers grow larger without significant change of orientation on glass, but whisker structures with less order were formed on gold. The fiber-like structure prepared at 100 °C has the highest electrical conductivity, which also implies that the stacking axis of the Pc macrocycle is the high conductivity direction. This characteristic also leads to quick response and higher sensitivity of this film to NO2. The effects of substrate temperature on the film characteristics and gas-sensing properties are compared to the heat-annealing effects observed in our previous work.
UR - http://www.scopus.com/inward/record.url?scp=0034831998&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0034831998&partnerID=8YFLogxK
U2 - 10.1016/S0169-4332(01)00019-8
DO - 10.1016/S0169-4332(01)00019-8
M3 - Article
AN - SCOPUS:0034831998
SN - 0169-4332
VL - 173
SP - 352
EP - 361
JO - Applied Surface Science
JF - Applied Surface Science
IS - 3-4
ER -