A steam reformer generates reformed gas by a steam-reforming reaction of hydrocarbon gas such as natural gas. The slider has an air bearing surface, a trailing face, and a mounting face opposite the air bearing surface. A current source is disposed at the current node while a differential diode-connected load is disposed between the differential pair and the voltage bus. Knowing the relative orientation between the ion beam and workpiece allows the workpiece to be oriented to a specific angle relative to the measured beam angle for more accurate and precise doping of the workpiece, which enhances semiconductor fabrication. The final result may be optionally blended with another data value and written to a memory device. The light emitting device includes a light emitting structure, a buffer layer on the light emitting structure, and a filter layer on the buffer layer.