Effect of Sintering Temperature on Electrical Properties of Chip on Glass Module with Direct Printing Method

摘要

In order to apply the direct printing method to the fabrication of chip on glass (COG) modules, we examined that the effect of the sintering temperature on the electrical properties of a COG module with direct printing method. Firstly, we fabricated an Ag conductive circuit on a glass substrate by the screen-printing method. To investigate its the effect on the electrical properties of the circuit, it was sintered at various temperatures, such as 150, 200, 250, and 300℃ for 30 min. Subsequently, we conducted Au electro-plating for the fabrication of a Si dummy chip. Finally, the flip-chip bonding process was conducted using anisotropic conductive film (ACF). The printed Ag circuits were well formed on the quartz substrate without any shorts or remarkable changes compared with the initial design. The electrical properties of the printed Ag circuits improved with increasing sintering temperature. The conductive particles in the ACF were well deformed in between the Au bumps and printed Ag pads after the bonding process. The four-point probe method was employed to measure the connection resistance of the joints constructed with the Au bumps on the Si chip and printed Ag circuit on the quartz substrate. The resistances of the interconnections drastically decreased with increasing sintering temperature, i.e., subsequently converged from 11.8Ω, to 7.36 mΩ.