Kyung-Man Kim

Nanoimprint template fabrication using wafer pattern for sub-30nm

Patterning of sub-30 nm features using high resolution nano-imprint lithography (NIL) requires use of quartz templates. To this end, various fabrication methods such as e-beam lithography, edge lithography, and focused ion beam lithography were employed for the template formation. Despite significant advances using these methods, NIL template formation process suffers from low throughput and high cost of fabrication when compared with the fabrication of masks used in optical lithography. This is largely owing to a 4X difference in feature sizes involved for the fabrication of NIL template and optical lithography mask. In this paper, we report on a simple, cost-effective method for the fabrication of sub-30 nm NIL templates. Typical fabrication-time required for the formation of sub-30 nm HP templates using conventional Gaussian beam electron beam lithography, runs into several days. Additionally, complicated etch procedures must be employed for pattern transfer onto quartz substrates. Here we propose a low cost, simplified fabrication process for the formation of high resolution NIL templates using wafer pattern replication. We fabricated sub- 30nmHP poly-silicon lines and spaces on silicon wafer using multiple patterning technique. These patterns were subsequently transferred onto quartz substrates using NIL technique. Several types of features were studied to realize a template using the triple patterning technique described above. Results of wafer printing using the said template will be discussed.

Adaptive color reproduction method to various users' monitor environment in color printer

In current printing technique, the Color Management System uses the ICC profiles of monitor and printer to perform color matching. Unfortunately the ICC profile cannot capture all of the monitor color reproduction characteristics, because such features change when the user acts on the color temperature, brightness and contrast controls, and they also depend on the kind of backlighting and lifetime of LCD monitor. As a result there is usually an unwanted color difference between an image displayed on the user monitor and its printed version. Yet, once we are able to produce an ICC profile that matches the users monitor characteristics by measuring, then the CMS becomes able to correctly perform color matching. However, this method is of difficult application, because in general the measuring equipment is not available and, even then, it takes a long time and new measurements according to monitor color temperature, brightness and contrast. In this paper we propose a color matching technique based on estimate of the users environment through the simple visual test with an output image on monitor and its printed image. The estimated characteristic of monitor is stored in new ICC profile and applied to color conversion process. Consequently the proposed method reduced the color difference between image displayed on user monitor and its printed image.