The presently disclosed technology provides a method for forming a structure wherein an electrode, such as a gate, comprising a refractory metal is deposited. A poly-last structure is formed for a display panel using an amorphous silicon or amorphous silicon compatible process. The hitting zone is at a predetermined and adjustable vertical height. The HUD also comprises a combiner. The heating causes carrier activation in the polysilicon layer and dopant penetration through the oxide layer into the channel region, thereby increasing the threshold voltage of the device. A method for oxidative dyeing of keratin fibers, comprising applying such compositions in the presence of an oxidizing agent, for a period sufficient to develop the desired coloration.