The present disclosure relates to devices and methods for enhancing the collection of charge carriers, such as electrons. Methods of manufacturing the devices are also disclosed. An electronic device can include a cathode, an anode, a gate electrode, and a focus electrode. The cathode can include a cathode substrate and an emitting region that is configured to emit an electron flow. The anode can include an anode substrate and a collection region that is configured to receive and/or absorb the electron flow. The gate electrode can be receptive to a first power source to produce a voltage in the gate electrode that is positively-biased with respect to the cathode. The focus electrode can be receptive to a second power source to produce a voltage in the focus electrode that is negatively-biased with respect to the gate electrode and/or the cathode.