硅表面直接生长十八烷基硅烷小分子自组装单层抗蚀剂的亚稳态氦原子光刻技术

Metastable helium atom beam lithography with octadecyltrichlorosilane self-assembled monolayer resister grown directly on silicon surface

选取不同尺寸和形状的物理掩模,以硅表面直接生长的十八烷基硅烷小分子自组装单分子层作为抗蚀剂,硅(100)为衬底,亚稳态氦原子作为曝光源,利用湿法化学刻蚀方法在衬底上制备具有纳米尺寸分辨率的硅结构图形。基于扫描电子显微镜、原子力显微镜的表征结果表明:原子光刻技术可以把具有纳米尺度分辨率的正负图形通过化学湿法刻蚀技术很好地传递到硅片衬底上,特征边缘分辨率达到20nm左右,具有较高的可信度和可重复性。正负图形相互转化的临界曝光原子剂量约为5×1014atomscm-2,曝光时间约为20min。

Metastable helium atom （He＊ ） beam lithography was utilized to pattern silicon surface using octadecyltrichlorosilane （OTS） self-assembled monolayer （SAM） grown directly on silicon surface as resister.The He＊ atom beam incident on the samples was patterned with stencil masks.Negative and positive pattern formations were observed for silicon （100） substrate with high fidelity.Negative and positive patterns were investigated with atomic force microscopy （ AFM） to evaluate the patterning quality such as edge profile.With a combination of atom beam lithography and wet-chemical etching method,the characteristic edge resolutions on silicon were successfully decreased to about 20 nm with high reliability and reproductivity.Results indicate a clear transition from positive to negative patterns at the critical He＊ dosage of about 5 × 1014 atoms cm -2 and the exposure time of about 20 min.