Figure 1

Scanning electron micrographs of uniform CN arrays with pitches of (a) 1 µm and (b) 5 µm (Scale bar: 10 µm). (c) Typical FE characteristics of a CN showing an excellent fit with FN theory for a 5 µm pitch array. (d) Variation in the field enhancement factor, β_FE, for 10 individual CNs at a pitch of 5 µm sowing a mean of 242 that is close to the predicted β ( = 240) inferred from the emitter geometry estimates. ±σ (7.5%) and ±2σ (15%) bands as illustrated.