Pure cinema is situated in terms of a larger aesthetic narrative that involves visual artists, theorists, intellectuals, and avant-garde filmmakers such as René Clair, Germaine Dulac, and Sergei Eisenstein. Hitchcock appears in this milieu in his relation to a German experimental cinema tradition, and most obviously in his work with F. W. Murnau at UFA studios from 1924 to 1925. The chapter traces pure cinema as an evolution of a silent cinematic ethos that championed pure form: shape, pattern, line, symmetry, and the freedom of expression of movement and time within a moving image medium.
This study introduced the SiC micro-heater chip as a novel thermal evaluation device for next-generation power modules and to evaluate the heat resistant performance of direct bonded copper (DBC) substrate with aluminum nitride (AlN-DBC), aluminum oxide (DBC-Al2O3) and silicon nitride (Si3N4-DBC) ceramics middle layer. The SiC micro-heater chips were structurally sound bonded on the two types of DBC substrates by Ag sinter paste and Au wire was used to interconnect the SiC and DBC substrate. The SiC micro-heater chip power modules were fixed on a water-cooling plate by a thermal interface material (TIM), a steady-state thermal resistance measurement and a power cycling test were successfully conducted. As a result, the thermal resistance of the SiC micro-heater chip power modules on the DBC-Al2O3 substrate at power over 200 W was about twice higher than DBC-Si3N4 and also higher than DBC-AlN. In addition, during the power cycle test, DBC-Al2O3 was stopped after 1000 cycles due to Pt heater pattern line was partially broken induced by the excessive rise in thermal resistance, but DBC-Si3N4 and DBC-AlN specimens were subjected to more than 20,000 cycles and not noticeable physical failure was found in both of the SiC chip and DBC substrates by a x-ray observation. The results indicated that AlN-DBC can be as an optimization substrate for the best heat dissipation/durability in wide band-gap (WBG) power devices. Our results provide an important index for industries demanding higher power and temperature power electronics.
In this paper, we studied stiction behavior of HAR pattern (line and space pattern) dependence on adhesion force with surface tension of drying liquid and surface contact angle. Surface tension effect was evaluated with various drying liquids such as IPA, ethanol and HFE (hydrofluoroether) chemical. Patterns treated by dHF, APM and surface modifier were introduced to investigate dependence of pattern collapse on contact angle. The high temperature D.I. water rinse followed by high temperatures drying using liquid with low surface tension was a most effective. Furthermore, surface modification method using HMDS (hexamethyldisilazane) chemical was also effective.
Photosensitive polymers are used extensively in the electronics industry to pattern line channels on silicon chips, ceramic substrates, and circuit boards. The photolytic process often requires an ultraviolet light exposure and subsequent bake to produce the required properties, prior to solvent development operations. An in situ FT-IR method was developed to assess the cross-linking reaction induced by UV exposure and investigate the effect of temperature on the overall reaction. The method employs a commercially available heated sample cell holder and an in-house fabricated fiber optic exposure tool. The UV-induced cure reaction was monitored as a function of time. The effect of bake temperature after exposure was also monitored.
Measurement of Heat Dissipation and Thermal-Stability of Power Modules on DBC Substrates with Various Ceramics by SiC Micro-Heater Chip System and Ag Sinter Joining