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:

X AR 600-50/2 is a new, sensitive and highly selective developer for high-tempered AR-P 617 layers (SB>180 °C). PMMA or CSAR 62 layers are not attacked, which is of particular importance for multilayer processes e.g., in the manufacture of T-gates.

顯影劑X AR 600-50/2是高選擇性及感度新顯影劑,適用於高溫軟烤(>180℃)AR-P 617阻劑. 但確不會攻擊PMMACSAR 62等阻劑.可用於製作T-gate的多層製程.

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

敏感度可透過顯影時間控制. 60 sec顯影時間,最低劑量約為70uC/cm2 . 3分鐘顯影,最低劑量約為約為40uC/cm2 , 6分鐘為25uC/cm2 10分鐘則降至約為20uC/cm2 .在長顯影時間可維持相當低的顯影損失.

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.

The following resist combination was evaluated at the Martin Luther University in Halle (AG Prof. G. Schmidt) with great success

T型閘極結構常見於各類型元件,如微機電,高電子移動率電晶體. 此奈米級結構多經由多層不同敏感度的阻劑,以電子束電子束微影製程相關圖案. 例如不同分子量的PMMA阻劑疊層,曝光再一次性顯影. 更精密的元件設計則建議採用不同種類阻劑的組合, 可避免塗層間互溶, 及選擇比適合的顯影製程,可達到高對比,精確的下切型結構.

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, 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; 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.