A handheld electronic device includes a reduced QWERTY keyboard and is enabled with disambiguation software. These steps are performed before the mesa structure is formed. A plurality of nozzle chambers is defined in the wafer substrate. The impeller includes a first set of impeller blades for transporting fluid through the pump chamber and a second set of impeller blades for creating a pressure force which pushes fluid away from the shaft opening. The thermal transfer sheet includes a substrate, a colorant layer provided on one surface of the substrate, and a heat-resistant slipping layer provided on the surface of the substrate opposite to the colorant layer, wherein the heat-resistant slipping layer contains at least a binder resin containing an amino group-containing acrylic resin and an epoxysilane, and a slipping agent.