A power-on circuit which may generate a power-on signal that is insensitive to the rising speed of an IO voltage or core voltage. The invention includes a tubular member comprising a body having a wall formed from a wrapped sheet of stock to define an interior wall and an exterior wall, a seam in the wall defining a first and second end of the wrapped sheet of stock, and a thread pattern stamped on the exterior wall. The methods include exposing metal-containing materials to halogen containing species in a substrate processing region. A sensor is mounted in the housing for receiving light reflected from the print media and generating electrical signals representative thereof. A support tube is coaxially aligned with the hydrogen permeable tube, wherein a gap space exists between the hydrogen permeable tube and the support tube in an area of overlap.