We report double-gated n-type silicon field emitter arrays with focus aperture diameter of 1.2 mu m, gate aperture diameter of 0.4 mu m, and tips that are 400 nm below the gate aperture. Focus transfer characteristics of the devices have three distinct regions of operation: a saturation region (V-F > 15 V) in which the anode current is almost independent of focus voltage, a rapidly increasing anode current region (5 V <= V-F <= 15 V), and a cut-off region (V-F < 5 V) in which there is no anode current. The anode current slope with respect to the focus voltage in the saturation region depends on the relative position of the tip to the gate, and it is very small if the gate screens the tip from the focus. The focus voltage at, which the anode current plateaus increased with the gate bias. We also report a negative transconductance region in the gate transfer characteristics for focus voltages in the rapidly increasing anode current region. The peak anode current and, the gate voltage at which it occurs increased with the focus bias. For focus voltages above 15 V, there was no negative transconductance region in the gate transfer characteristics. The negative transconductance region is explained by the initial spread in the axial velocity (energy) of electrons leaving the tips. The cut-off region is attributed to the formation of a potential barrier between the tip and the anode. (c) 2006 American Vacuum Society.