NOVELTY - Recovering silane from the off-gas of a chemical vapor deposition (CVD) reactor (100) involves contacting at least a portion of the off-gas with silicon particles at an elevated temperature; removing gas species having normal boiling points less than 100 degrees K from the off-gas to increase the concentration of the silane; and purifying the remaining silane stream.    USE - For recovering silane from the off-gas of a chemical vapor deposition (CVD) reactor (claimed) in thin film process for the production of semiconductor devices such as large scale integrated circuits, flat panel displays, and thin film solar cells.    ADVANTAGE - The method is safe for the recovery of by-products and increases the concentration of silane species.    DETAILED DESCRIPTION - Recovering silane of formula SixH2x+2 from the off-gas of a chemical vapor deposition (CVD) reactor (100) involves contacting at least a portion of the off-gas with silicon particles at an elevated temperature; removing gas species having normal boiling points less than 100 degrees K from the off-gas to increase the concentration of the silane; and purifying the remaining silane stream.    x=not defined.    An INDEPENDENT CLAIM is included for an apparatus for recovering silane of formula SixH2x+2 from the off-gas of a chemical vapor deposition (CVD) reactor (100) involving the CVD reactor having a process gas feed (110), a nitrogen gas feed (112) and a discharge (114); a waste treatment system communicating with the discharge of the CVD reactor; a recovery system communicating with the discharge of the CVD reactor; and a diversion to send the off-gas from the CVD reactor to the waste treatment system when the concentration of SixH2x+2 in the off-gas is too low to warrant recovery, and to send the off-gas from the CVD reactor to the recovery system when the concentration of SixH2x+2 in the off-gas warrants recovery, where the recovery system comprises a silicon bed, unit to heat the silicon bed, a concentration device (140) communicating with the silicon bed, and a purification device communicating with the concentration device.    DESCRIPTION OF DRAWING(S) - The figure shows a block diagram of method to recover silane products from a chemical vapor deposition reactor off-gas.    Chemical vapor deposition reactor (100)    Gas feed (110)    Nitrogen gas feed (112)    Discharge (114)    Concentration device (140)    Purification device (150)