To verify the effectiveness of our method, under the optimal exposure parameters, we exposed the high-resolution resist PMMA (100-nm thickness, coated on silicon that was mounted beside the wafer coated with nitrocellulose) at line dose of 400 to 3,300 pC/cm.
Experimental results show that the temperature sensor with high resolution can resist high-voltage and electromagnetic interference, and has high sensitivity and precision with 1000 Hz/°C.
The patterns are first printed (at 1×) on a 300 mm wafer using a Vistec VB300 electron beam lithography tool with a high resolution HSQ resist (commercially known as Dow Corning XR-1541).
As both PMGI (using solvent developers) and ZEP-520A are high-resolution resists with high contrasts [8, 9], smaller features could be fabricated using the current process.
First, electron beam lithography is used to pattern a high-resolution inorganic resist, hydrogen silsesquioxane (HSQ), in order to fabricate tiny nanopillars with high aspect ratio, up to 7.5, in 150-nm HSQ thickness.
In order to investigate the high resolution capability of nitrocellulose resist, periodic line array with a period of 600 nm was exposed at 20 keV over a broad line dose range and subsequently coated with 30 nm Cr for SEM imaging.
EBL was performed in the high resolution hydrogen silsesquioxane (HSQ) inorganic resist.
Hydrogen silsesquioxane (HSQ) is a high resolution negative-tone electron beam resist allowing for direct transfer of nanostructures into silicon-on-insulator.
Note that even thinner resist was used for most previous high resolution studies on HSQ and calixarene resists.
Upon UV irradiation, the resist film produced high resolution negative tone patterns.
Thin resist is generally used for high resolution patterning in to reduce the effect of capillary force during resist drying, which leads to pattern collapse (unless using critical point drying [12]), and the forward scattering of electrons that is more serious for thicker resist [13].
