Positive E-Beam Resist AR-P 6200series (CSAR 62)High resolution high contrast EBL resists for integrated circuit & masks
Application examples for CSAR 62
Developer for T-gate applications with AR-P 617：
The sensitivity can easily be controlled via the duration of the development. At a development time of 60 s, the dose to clear is about 70 μC/cm2, after 3 minutes of development about 40 μC/cm2, after 6 minutes 25 μC/cm2, and after 10 minutes about 20 μC/cm2! The amount of dark erosion is very low, even at longer development times
T-gates with three-layer system CSAR/PMMA-co-MA/PMMA
T-gate structures are often required for the fabrication of electronic components (MEMS, HEMTs). Corresponding nanostructures can be realized via e-beam lithography in multi-layer processes. Generally, resist layers with different sensitivities like e.g., PMMAs with varying molecular weight distributions are coated on top of each other, irradiated with electrons and then developed in one step. For the production of more defined architectures, it is however advantageous to combine different types of resists. In this case, not only the mixing of the different layers during coating can be avoided, but also the use of selective developers is possible. As a result, high contrasts and accurate undercuts can be achieved.
下圖為德國大學教授(Martin Luther University in Halle / AG Prof. G. Schmidt)以下列阻劑的組合,成功的獲得精密圖案
CSAR 62 was used as top layer; the development was carried out with AR 600-546 (amyl acetate). In this high-contrast developer, CSAR 62 and also the lower layer consisting of 950k PMMA (AR-P 679.03) has a relatively low sensitivity. In the intensively irradiated (30 kV) central area, nevertheless a complete development of all layers is achieved.
Subsequently, the undercut in the middle layer (PMMA-co-MA 33, AR-P 617) can be produced in a second development step with X AR 600-50/2.
頂層為CSAR 62, 以AR 600-546(乙酸戊酯)顯影,對比率高. 最底層為PMMA 950k, 敏感度相對教低; 在30kV加速電壓下曝光,三層結構都可顯開.
PMMA-co-MA阻劑在中間層, 在第二階段以X AR 600-50/2顯影,可形成如圖2所示的內切結構.
The special developer X AR 600-50/2 selectively develops the middle layer. The three-layer process as described above enables the fabrication of three-dimensional nanostructures with high contrast in only one electron exposure. The process window is wide, and the shape of the undercut as well as the geometry of the lower PMMA layer can be easily modified. After metallization and lift-off, T-gate architectures as well as nanoscale metal bridges could be realized.
X AR 600-50/5是特殊的顯影劑,選擇性的只顯影中間層. 上述三層阻劑製程只需一次電子束曝光即可形成立體的奈米結構. 製程穩定, 且容易調整下層(PMMA)與中間層(PMMA-co-MA)內切的結構. 經金屬沉積與懸浮剝離, 即可形成T型閘極極奈米級金屬橋等結構.