Structure-Designable Formation-Method of Super Low-k SiOC Film (k=2.2) by Neutral-Beam-Enhanced-CVD
Ar neutral beam enhanced chemical vapor deposition can control the dielectric constant and film modulus of low-k SiOC deposited on Si substrates precisely because it avoids precursor dissociation due to electron collisions and UV photons in plasma. Optimizing the ratio between Si-O and Si-(CH3)x as well as the proportions of linear, network, and cage Si-O structures by changing the precursor, we obtained a k of 2.2 and a reasonable modulus by using either dimethyl diethoxy silane or dimethyl dimethoxy silane as a precursor.
Low dielectric constant insulator formed by downstream plasma CVD at room temperature using TMS/O2
We present an insulator with a dielectric constant lower than 3.0, thermal stability up to 500° C and good gap-filling characteristics. This insulator was formed by downstream plasma chemical vapor deposition (CVD) at room temperature using tetra-methylsilane (TMS)/O2 gases. It contained a large amount of water in the as-deposited state. Annealing at 350° C resulted in a decrease in the water content of the insulator, and the insulator did not absorb water after the annealing. The film is constructed from Si–O and Si–CH3 bonds, which produce a low dielectric constant and high thermal stability.
Urban Identities and Catastrophe: Izmir and Salonica at the End of the Ottoman Empire*
Two huge fires dramatically influenced the urban development of Salonica and Izmir, in 1917 and in 1922, respectively. These catastrophes occurred after the Ottoman Empire fell, and Salonica and Izmir had shifted into new national contexts. The fires mainly destroyed the districts that were transformed during the late‐Ottoman period. These districts became the cosmopolitan façades of modern Izmir and Salonica. The post‐fires' tabula rasa provided an opportunity for Greek and Turkish politicians and European planners to change the urban identity of both cities. Moreover, the Lausanne Treaty of 1923 transformed their multicultural societies also. Reconstruction plans had been thought to de‐Ottomanize and remove the previous idea of the towns and their multiplicity, interpreting new cultural and nationalist feeling. Here, I emphasize how modernity was interpreted before and after the fires, and point out contradictions between ideological aspects of planning and how the first urban districts were built during the 1920s.