High-resolution electron microscopy requires electron beams with high-brightness. Hence, the authors used a resist-assisted patterning process to fabricate a new high-resolution cold-cathode electron beam with carbon nanotube (CNT) electron emitters. Herein, the authors successfully prepared one free-standing CNT emitter containing no impurities. The authors calculated the electron beam properties of the CNT emitter and found a reduced brightness of 1.7 × 107 A m−2 sr−1 V−1 at a current of 1.5 μA with a spatial resolution of 50 μm in a diode configuration. The one free-standing CNT emitter cold-cathode electron beam could be applied to a variety of electron microscope devices.

Carbon nanotube (CNT)-based cold cathode has been used as an efficient electron emitter owing to its high electrical conductivity and unique structural feature of high aspect ratio. However, conventional CNT-based cold cathode with diode electrode configuration restricts the applicable range of the CNT cold cathode. Here, we present the systematic investigation of electron beam property and I–V characteristic of various CNT-based multi-emitter system for advanced electron emitting devices capable of large areal applications. Single emitter island, consisting of well-defined N × N CNT strands, shows high maximum current value, low turn-on voltage and large electron beam diameter with increase of N value. For the multi-emitter system consisting multi-islands, a critical pitch size of multi-emitter system is found to obtain separated electron beam for each island without significant interference between electrons departing from each island.