NOVELTY - Workpiece is treated with vaporous elements by introducing the work piece and an element-containing material to an enclosure, heating the work piece, heating the element-containing material to volatilize the element and release an element-containing vapor into the enclosure, reacting the element-containing vapor with the workpiece, regulating the temperature of the element-containing material to condense the element from the element-containing vapor on the element-containing material, and cooling the work piece.    USE - For treating a workpiece, e.g. photovoltaic precursor, with a vaporous element to produce thin film Cu (In,Ga)(S,Se) (CIGSS) or CIGS solar cells.    ADVANTAGE - The method provides an independent control of substrate temperature, a high utilization rate of selenium of greater than or equal to90%, a high throughput capability with enhanced thermal management, controlled release and capture of selenium to the same place repeatedly, independent control of the vapor pressure delivery of sulfur or selenium, vacuum compatible selenium delivery and temperature control, distinct temperature zones and valves to allow use of traditional elastomer seals and vacuum gauges, and future process automation upgrade capability.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for:    (1) an apparatus for treating a work piece with a vaporous element;    (2) a method for preparing a treatment chamber for treating a work piece with a volatilizable element;    (3) a treatment chamber isolation apparatus, comprising a sealing assembly comprising a support structure, cover plate adapted to engage the treatment chamber opening, rods having a first end adapted to engage the support structure and a second end adapted to engage the cover plate, and compressor for the sealing assembly against the treatment chamber where the cover plate engages the treatment chamber opening to provide isolation of the treatment chamber;    (4) a material delivery device comprising a cylindrical body having outer surface, a volatilizable material applied to the outer surface, and unit for varying the temperature of the outer surface to regulate the volatilization of the volatilizable material;    (5) a method of delivering a volatile material, comprising providing a cylindrical body having an outer surface, applying a volatilizable material to the outer surface, and regulating the temperature of the outer surface to vary the amount of material volatilized;    (6) a treatment chamber valve actuation device comprising an actuation plate, actuation rod mounted to the actuation plate, an actuator, and a flexible plate mounted between the actuation plate and the treatment chamber;    (7) a photovoltaic cell comprising a substrate, and an absorber deposited on to the substrate, the absorber comprising group 11, 12 or 13 element, and less than 5% hydrogen; and    (8) a method of fabricating a low-hydrogen containing photovoltaic cell from the substrate and absorber.    DESCRIPTION OF DRAWING(S) - The figure is a perspective view of a treatment furnace.    Furnace (50)    Plate (53)    Hinge assembly (66)    Hinge element (70)    Clamps (72)