We introduce a state-of-the-art patterning process developed by new patterning technology using Atomic Layer Deposition (ALD) towards 5/7 nm generation. In the patterning process, critical dimension (CD) shrink technique without CD loading is one of the key requirements. However, in the conventional CD shrink technique, CD loading canʼt be solved in principle. To overcome this issue, by integrating ALD process into the etching flow, we developed a new CD shrink technique without causing CD loading. Furthermore, CD shrink amount can be precisely controlled by the number of ALD cycles while keeping the excellent CD shrink uniformity across a wafer. This is obtained by utilizing a conformal layer with characteristics of ALDʼs self-limiting reaction, which is independent of the pattern variety.
High power pulsed magnetron sputtering (HPPMS) is a variant of sputtering deposition method in that pulsed power is applied to the sputtering target with low repetition frequency and small duty ratio. It produces high density plasma intermittently which enables the ionization of sputtered atoms and the control of their energy and direction by introducing potential difference between the plasma and the substrate. We have proposed two HPPMS techniques which can control the plasma potential. One is to modify the target voltage waveform where the positive voltage is applied during the “pulse-off” period. The other is to use the triode configuration in which a positively-biased electrode is added. Positive plasma potential could be confirmed experimentally, and dense film structures and smooth surfaces could be obtained by these methods. It suggested that the ionized atoms impinged on the growing film surface with accelerated kinetic energy.
Back-contact c-Si solar cells can realize superior performance due to no shadowing loss. Surface passivation with excellent quality is required for achieving sufficient conversion efficiency in the back-contact cells. Cat-CVD can produce high-quality passivation films owing to its plasma-damage-less nature. SiNx deposition at a low temperature and successive post annealing leads to a surface recombination velocity (SRV) of < 5 cm/s. The exposure of c-Si wafers to catalytically generated phosphorus radicals can form ultra-thin highly-doped layers (Cat-doping). This P-doped region acts to reduce an SRV to < 2 cm/s by combining with a Cat-CVD SiNx film. We have also established the passivation of rear c-Si surfaces by Cat-CVD a-Si with suppressing epitaxial growth by introducing ultra-thin oxide layers formed by dipping in H2O2. The formation of doped a-Si by Cat-doping has also been demonstrated, which will be applicable to the formation of patterned doping regions in Si heterojunction back-contact cells.
The unique properties of diamond like carbon (DLC) film, including its chemical inertness and impermeability, make it possible for new applications in food and beverage. In this paper, I summarize and review the recent progress of gas barrier enhancement of polyethylene terephthalate (PET) bottles for beverage from the view point of the application of DLC coating. A unique technique of plasma CVD method has been developed to deposit DLC layer on the inside surface of PET bottles. The DLC-coated PET bottle exhibits extremely high gas barrier properties against oxygen, carbon dioxide and flavors compared to conventional bottles. For the practical use of PET bottles as a commodity, machines have been introduced for soft drink, wine, Japanese sake, edible oil, seasonings and others.