[雙語翻譯]外文翻譯--樹脂粘度與壓印壓力模式之間的相關關系（英文）

1、Electron. Mater. Lett., Vol. 9, No. 6 (2013), pp. 793-796Correlation between Resin Viscosity and Imprinting Pressure ModeSiyoul Jang,1,* Jae-Gab Lee,2 and Heon Lee31School of Mechanical and Automotive Engineering, Kookmi

2、n University, Seoul 136-702, Korea 2School of Advanced Materials Engineering, Kookmin University, Seoul 136-702, Korea 3School of Advanced Materials Engineering, Korea University, Seoul 136-701, Korea(received date: 13

3、October 2012 / accepted date: 9 January 2013 / published date: 10 November 2013)The changes in the period of the imprinting process were studied by changing resin viscosities and imprinting pressure mode. If an imprintin

4、g process is required to achieve a proposed level of residual resin thickness or win- dow open, an appropriate process period should be assigned with respect to the magnitude and rate of the imprinting pressure because t

5、he residual layer thickness (RLT) is significantly influenced by these factors. Fur- thermore, the impact of resin viscosity on RLT variation is as significant as that of the imprinting pressure mode. We performed a nume

6、rical simulation using a mold having repetitive elliptical protrusions with a pattern density of 12.03% to determine the influence of the considered process factors on the imprinting process period.Keywords: residual lay

7、er thickness, imprinting pressure, lubrication, window open1. INTRODUCTIONUV imprinting is widely used in various manufacturing processes, and the importance of its production efficiency in recent mass-production applica

8、tions has become greater. It has been demonstrated experimentally that the processing period of UV imprinting depends on resin viscosity, and the magnitude and rate of imprinting pressure (pressure mode) before UV curing

9、.[1] For imprinting a UV resin film with zero residual layer thickness (RLT), resin viscosity and imprinting pressure mode are the major process factors determining the processing period. In particular, resin viscosity d

10、irectly influences not only mold design in terms of pattern density and protrusion ratio but also imprinting pressure modes. In the case of sub micro-scale UV imprinting with a high-viscosity resin of thin film status, f

11、low resistance, which is high because of the thin film mechanism, warrants high imprinting pressures, eventually resulting in mold deformation.[2] Especially in zero residual layer imprinting, the imprinting pressure is

12、maintained for a long duration, thereby increasing the possibility of mold deformation. To avoid this situation, the mold size should be smaller, and its compliance must be increased for patterning evenness.[3-6]Regardin

13、g the viscous behaviors of UV resins in the mold cavity, most simulation studies simply select a constant imprinting velocity, constant applied imprinting pressure, and constant force, which is not possible with a real i

14、mprinting system.[6] The window opening process, which isgoverned by both the imprinting pressure and the resin viscosity for achieving zero RLT, can mostly be manipulated by varying the applied imprinting pressure.[4] H

15、owever, most imprinters cannot impose the desired imprinting pressure in the direct mode as soon as the equipment is started. The imprinting pressure thus gradually increases to its final value over the duration of the p

16、rocess. Many recent simulation studies[6,7] have computed RLT variations during imprinting by considering optimized cavity and protrusion distributions on the mold surface. In correlation works between experimental and

17、numerical analysis results,[8,9] resin viscosity, one of the most significant imprinting process parameters, is considered to be very high in thin film status, for instance, ~104 Pas in numerical analyses. In this study

18、, using a repetitive 2-D pattern feature, we simulate resin pressure developments and RLT variations during imprinting based on imprinting pressure modes and resin viscosities. The results show distinct differences in RL

19、T variations under different imprinting conditions.2. RLT VARIATIONS UNDER DIFFERENT RESIN VISCOSITIESIn UV imprinting systems, resin viscosity is controlled to be small (~10 mPas) in order to ensure quick and complete

20、filling of the cavity as well as to dispense the resin over the substrate during short process time. However, the resin fluid film coated over the target has considerably high viscosity (for instance ~104Pas) because of

21、the thin film effect. To arrive at a suitable value of imprinting resin viscosity at thin film status, the RLT can be measured as a function of theDOI: 10.1007/s13391-013-6013-7*Corresponding author: jangs@kookmin.ac.kr

22、©KIM and SpringerS. Jang et al. 795Electron. Mater. Lett. Vol. 9, No. 6 (2013)influence on the RLT variations and is one of the major process design factors, as explained before. For the mold pattern considered in t

23、his study, under an imprinting pressure of 1.0 bar, RLT decreases very slowly at a resin viscosity that is 10× higher than 1.0 × 104 Pas. The 1.0 × 105 Pas resin takes 120 s to achieve 20 nm RLT, whereas t

24、he 1.0 × 104 Pas resin does the same in 13 s (Fig. 3). Understandably, higher imprinting pressure results in a faster RLT decrease as long as the imprinter can quickly reach the steady pressure value. Figure 3 shows

25、 the RLT variations under steady pressures of 1.0 bar and 10.0 bar for a 3 s transient period. In this case, we found that theimprinting pressure has a direct influence on the RLT variation, similar to the characteristic

26、s of resin viscosity, which also determines the imprinting process design. The detailed pressure development under imprinting conditions of 1.0 × 104 Pas and a 8.0 s transition period for a 1.0 bar steady pressure

27、is shown in Fig. 4. Initial resin pressure developed in the center of the imprinting area and grows gradually over the entire area. As the imprinting progresses, the developed pressure causes the resin to take a shape si

28、milar to that of the mold pattern; this process is closely related to pattern density. Long after the steady imprinting pressure is reached, the pressure on each protruded part of the mold becomes higher, and this higher

29、 pressure squeezes the resin fluid out of the contact area, leading to the formation of a zero residual layer.4. CONCLUSIONSPressure development was simulated numerically with a repetitive mold pattern. A sufficiently la

30、rge computational area size was considered for the repeated pattern shape. Resin viscosity, imprinting pressure, and pressure rate were selected as the main factors in designing the imprinting process. In the simulation,

31、 the pressure mode reasonably reflects the imprinter’s operation behaviors, one of which controls the imprinting force rather than the squeeze velocity. Pressure development was investigated numerically as a function of

32、 the imprinting pressure, pressure rate, and viscosity. We found that each of the considered parameters has unique development patterns, which can provide information for achieving a better window opening process. The ef

33、fect of high imprinting pressure is similar to that of low resin viscosity, whereas the effect of low imprinting pressure is similar to that of high resin viscosity. However,Fig. 2. RLT variations based on imprinting pre

34、ssure rates under 10.0 bar and 1.0 × 104 Pas viscosity.Fig. 3. RLT variations under 1.0 and 10.0 bar of 1.0 × 104 Pas viscos- ity and 10 bar of 1.0 × 104 Pas.Fig. 4. Pressure development variations under 1