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Hexaazatriphenylene (HAT) derivatives have attracted wide attention because of their electron‐deficient nature and unique self‐assembly properties. In this work, a facile synthesis method for obtaining HAT derivatives with alternating electron‐withdrawing nitrile and electron‐donating alkoxy groups (HATCNOCn) is proposed. Crystal structure analysis indicated that HATCNOCn forms a one‐dimensional columnar structure via strong π–π interactions. Density functional theory calculations revealed that the edge of HATCNOCn is divided into positively and negatively charged sites owing to the presence of alternating nitrile and alkoxy groups, which would induce strong π–π interactions. Thermal analysis and polarizing optical microscopy revealed that HATCNOCn exhibits columnar liquid‐crystal phases. Time‐resolved microwave conductivity measurements further demonstrated the photoconductive nature of HATCNOCn. The proposed strategy could provide a new strategy for the design of novel organic semiconductive materials.

Nitrogen ion implantation was performed on CoCrPt–SiO2 perpendicular media with a resist mask to fabricate patterned media. Signal amplitude and autocorrelation signal-to-noise ratio of the preamble pattern were measured to evaluate the quality of the pattern fabricated by the ion implantation. The signal-to-noise ratio and the jitter were closely related to the saturation magnetization of the ion-implanted area. The remained magnetization of the ion-implanted area probably affects edge roughness of the magnetic pattern. Larger reduction of the saturation magnetization at the ion-implanted area is important for obtaining higher signal quality. Off-track profiles and 747 curves were measured for 76-nm-pitch discrete track fabricated by ion implantation. The results show that discrete track recording had advantages over recording on continuous magnetic film, which indicates that the fabricated patterns were successfully isolated. The nitrogen ion implantation was effective in fabricating isolated magnetic tracks or isolated magnetic dots for the patterned media.

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The relation between hydroggn contents in DLC overcoat of a hard disk medium and its head flyability was studied. The effbct of additiona1 gasses such as N2 and N20 was also investigated. It was, found that the hydrogen content in DLC affects the magnetic head fiyability and it is effectiye to add NiO in the atrnosphere of DLC deposition process not only to obtain sufficient amourit of functional groups but also to rgduce hydrogen content of the DLC overcoatThe results of･glide test showed drastic improvement of head flyability by decreasing the hydrogenlcarl)on ratio.