Direct self-assembly (DSA) can form periodic fine patterns by the repulsive forces between different polymers. As one of the candidates for next-generation lithography, it has been evaluated for semiconductor manufacturing processes for the past 10 years1-11 . Reports of DSA processes using Chemo-epitaxy show many line-and-patterns formed using lamellas and few hole patterns using cylinders. The reason why it is difficult to form a hole pattern is that the direction of line-and-space misalignment is one-dimensional, whereas in the case of a hole, it is two-dimensional, so dislocation defects are likely to occur and process control is difficult. On the other hand, the pitch of hole patterns in semiconductor devices is shrinking year by year, and in the future it may not be possible to form them all at once even with EUV (Extreme ultraviolet) lithography. Therefore, it is expected that there will be an increasing demand for shrinking patterns using DSA additionally. In this presentation, we report on the method of forming a hole pattern by the chemo-epitaxy process and the process condition setting, and discuss the possibility of application to the semiconductor process.
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