| KIST's ultra-fine nano-pattern production technology,
| Exploiting the self-assembly properties of block copolymers
| Vertical alignment formation is possible even under different process conditions

A research team led by Dr. Jeong-Gon Son of the Photoelectronic Hybrid Research Center at the Korea Institute of Science and Technology (KIST) has improved the nano-patterning technology used in the manufacture of semiconductor chips and photoelectric devices.

Dr. Son's team announced on July 22 that they have developed an ultra-fine nano-pattern manufacturing technology of less than 10 nm (nanometers) that is easy and simple to use and can be applied to various types and shapes of block copolymers. A block copolymer refers to a polymer in which two or more polymers are regularly linked to a single polymer chain.

Recently, the importance of ultra-fine pattern manufacturing technology at the 10nm level is increasing as a process for next-generation semiconductors. In particular, the micro-patterning technology that utilizes the self-assembly characteristics of block copolymers to create nanostructures on their own is gaining attention as a next-generation nano-patterning technology because it can obtain large-area ultra-fine nano-patterns inexpensively and quickly, unlike the expensive and complex extreme ultraviolet (EUV) process.

Until now, there have been technical limitations in the process of creating nanopatterns using block copolymers, such as removing structural defects and aligning patterns.

When producing block copolymers at sizes below 10 nm, there was a limitation that vertical orientation required for pattern transfer was difficult.

Previously reported studies have used complex and difficult processes, such as synthesizing random polymers and introducing them to the top and bottom of the film each time in order to implement vertical alignment for a specific block copolymer, which has resulted in significant limitations in applying them to actual processes.

Dr. Son's team used a plasma treatment method that introduced a filter to allow only low-energy particles to pass through, thereby causing only physical collisions with the polymer film, thereby forming a thin chemical bonding layer of 3 to 5 nm on the surface.

This process is introduced into block copolymer films to create a thin layer in which the two polymers are well mixed, and this layer naturally forms a neutral interface with the block copolymer below, thereby forming a vertical It made me have a sense of direction.

This process demonstrated that vertical alignment formation was possible not only for block copolymers of various types and shapes, but also under various process conditions.

Using this technology, the KIST research team was able to implement a three-dimensional structure that mimics a FinFET, which is used as a three-dimensional stereoscopic transistor in actual semiconductor processes, and also showed that a vertical stripe pattern of less than 10 nm with almost no defects can be formed on a fine chemical pattern.

Dr. Jeong-Gon Son said, “This achievement is significant in that it very simply solves the issue of orientation control of block copolymers that can be used universally, which was considered a difficult problem until now,” and “We expect that this sub-10nm patterning technology through induced self-assembly will be practically applied as an ultra-fine semiconductor process technology.”

Meanwhile, the results of this study were published in the latest issue of Nature Communications, a sister journal of the world-renowned scientific journal Nature.