Exhaust hood in a CVD reactor

The invention relates to an apparatus for exhausting a process gas from a CVD or PVD reactor having a flow channel having suction-extraction element (1), wherein the flow channel a suction port (2), a in a flow direction (S) adjoining Gasansaugraum (3) and in the flow direction (S) after the Gasansaugraum (3) arranged in a suction line (4) opening into the gas collection space (5), said extending in a long-side direction (L) extending the length of the suction opening (2) is substantially greater than the width and wherein the Gasansaugraum (3) and the gas collection space (5) in such a manner of extending in the longitudinal side direction (L) extending lengthwise side winches (6, 8) and in the narrow side direction (W) extending narrow side walls (7) are limited, that generated as a result of the suction pipe (4) under pressure in the flow channel forming a gas flow. arranged in at least one between Gasansaugraum (3) and gas-collecting chamber (5) gap (9) are flow-influencing structures provided, arranged in a midway between the narrow side walls (7) Central zone (Z) has a greater flow resistance to the gas flow exercise as in between the central zone (Z) and the narrow side walls (7) arranged in the edge zones (R).