Low-dielectric-constant (k < 2:0) nonporous fluorocarbon films are formed using a new microwave-excited low electron temperature and high-density plasma system with a dual-shower-plate structure. In the new system, the material gas (C 5 F 8 ) is supplied by a lower shower plate inserted in the diffusion plasma region of very low electron temperature (around 1-2 eV). An upper shower plate is used for supplying the plasma excitation gas in a uniform downflow in the chamber. Since such a gas flow pattern can prevent the penetration of the material gas into the plasma excitation region, the overdecomposition of the material gas can be markedly suppressed as compared with that in the case of using conventional plasma systems such as an electron cyclotron resonance (ECR) plasma source. As a result, fluorocarbon films can be formed by maximizing the original characteristics of material gases. The fluorocarbon films formed using the new system have not only low k but also low leakage current density, sufficient mechanical strength, strong adhesion, high heat resistance and good surface smoothness. Therefore, such films can be used in interlayer dielectrics in ultralarge-scale integration (ULSI) devices.
The radical reaction based semiconductor manufacturing has been applied to silicon device process. Such as SiO2 and Si3N4 can be formed at low temperatures of under 500–600 °C. In this study, we applied radical reaction based semiconductor manufacturing to compound semiconductor of ZnO. The characteristics of ZnO films grown by a newly developed plasma enhanced metal organic chemical vapor deposition (MOCVD) employing microwave excited high-density plasma are good. The film formed on a-plane sapphire is epitaxially oriented in c-axis direction, and the composition is similar to ZnO substrate grown by hydrothermal method. The mobility of grown film at around 400 °C is 23 cm2/(V·s), and it is increased to 46 cm2/(V·s) by 700 °C annealing. The carbon concentration in the films can be reduced by the selection of a zinc precursor and the optimization of process conditions. The active species of plasma are effective for the crystallization of films.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.