Abstract: A clean air room for a semiconductor factory includes a plurality of clean air boxes placed in side-by-side relation and each designed for its own processing step, an air conditioning equipment including a fresh-air regulator for controlling a supply of fresh-air to the clean air boxes, and fan filter units for supplying the air under pressure, the clean air boxes having clean air chambers of which environment is maintained to a predetermined degree of cleanliness in response to the fan filter units and defining an air circulating path extending through the clean air chambers, the clean air chambers including low clean air chambers and an ultra clean air chamber divided by common side walls of the clean air boxes, the low clean air chambers having operating zones and the ultra clean air chamber having a transfer robot therein, and semiconductor processors extending through the common side walls and having processing stations, the processing stations being located at least within the ultra clean air chamber.

Abstract: In semiconductor production plants a highly clean state is required. In a plant building, through which air is forcibly circulated, a clean room in a low or medium cleanliness state is formed using a filter. A plurality of processing units are provided in the clean room and held in a high cleanliness state. A transport robot transfers a workpiece or like object to and from each processing unit. The robot is capable of being driven to positions corresponding to the processing units and holds the workpiece or object in a highly clean state. Thus, there is no need of holding the entire building highly clean, and only a required part of the building may be held in a highly clean state, which is advantageous from the standpoint of cost.