The effective sensing area is the key point of solid-state nanopore single-molecule detection, which is determined by the diameter of the hole and the thickness of the membrane. High spatial resolution can be achieved by using single-atom thickness two-dimensional materials, such as single-layer graphene and molybdenum disulfide. Helium ion beam microscopy provides an effective technique for manufacturing small-sized nanopores. Here, we show that the precise fabrication of sub-2 nanometer nanopores has been successfully achieved on a single-layer graphene film, which provides the best spatial resolution in room-temperature ionic liquid-assisted single-molecule detection. Many graphene nanopores of different sizes have been fabricated, with a minimum pore diameter of 1.4 nm. The application of these graphene nanopores manufactured by HIM shows that single-layer graphene nanopores can distinguish different homopolymer single-stranded DNA lengths and types, and can even identify four single nucleotides.

有效传感面积是固态纳米孔单分子检测的关键点，由孔的直径和膜的厚度决定。通过使用单原子厚度的二维材料，如单层石墨烯和二硫化钼，可以获得高空间分辨率。氦离子束显微镜为制造小尺寸纳米孔提供了一种有效的技术。在这里，我们展示了在单层石墨烯薄膜上成功实现了亚 2 纳米纳米孔的精确制造，这在室温离子液体辅助单分子检测中提供了最佳的空间分辨率。已经制造了许多不同尺寸的石墨烯纳米孔，最小孔径为 1.4 nm。