tailieunhanh - Engineering Materials and Processes phần 5

Điện trở suất tương đối cao hơn giá trị của màng mỏng Ag được thực hiện trong nghiên cứu này khi so sánh với bạc số lượng lớn là kết quả của tán xạ bề mặt hơn do độ dày của nó và kết hợp chặt chẽ của một lượng nhỏ oxy trong quá trình màng mỏng. (Al) Ag màng mỏng, điện trở suất của mẫu ủ ở 400 ° C trong 1 giờ trong chân không là giảm từ giá trị các mẫu như lắng đọng. | Thermal Stability 47 Anneal Temperature C Figure . Electrical resistivity of Ag Ag Al -I and Ag Al -II thin films on SiO2 substrates annealed at various temperatures in vacuum for 1 hour 6 The relatively higher resistivity value of Ag thin film made in this study when compared to bulk silver resulted from more surface scattering due to its thickness and the incorporation of a small amount of oxygen during the thin film process. For the Ag Al thin films the resistivity of samples annealed at 400 C for 1 hour in vacuum is decreased from the value of as-deposited samples. It is thought that the enhancement of crystallization and grain growth of thin film obtained by the X-ray diffraction analysis shown in Figure contribute to the decrease of resistivity. The resistivity of both Ag Al -I and Ag Al -II thin films is constant after annealing at 400 C. The difference of absolute value of resistivity between two different Ag Al thin films has also remained constant. This means that the Ag Al on SiO2 is a thermally stable solid solution as confirmed by RBS XRD and optical microscopy. For pure Ag thin films the resistivity of the sample annealed at 400 C for 1 hour in vacuum is decreased slightly due to the crystallization and grain growth although agglomeration is started. However resistivity is increased abruptly from 500 C. The Ag thin film on SiO2 annealed at 600 C for 1 hour in vacuum has infinite resistivity since the scattering effect of conduction electrons is increased. The conduction path is reduced and lost eventually. This fact is consistent with RBS microstructure analysis explained above. The interesting fact is that the resistivity of Ag Al -II thin films annealed at 400 C is lower than that of pure Ag thin film annealed at the 48 Silver Metallization same temperature. The finding is a direct result of the good thermal stability of Ag Al thin films on the SiO2 layer. The thermal stability of Ag thin films on SiO2 substrates is enhanced by the addition .