a buffer station provides potential improvement for the operation of a facility . by storing to - be - accessed workpieces in the buffer stations of an equipment , the operation of the facility is not interrupted when the equipment is down . the workpieces can be retrieved through emergency access port of the buffer station , thus ensure the continuous supply of workpieces for the workpiece flow of the facility . algorithm for getting the needed workpieces to the buffer station is also provided through a controller or a computer mechanism . the buffer station can be incorporated in a stocker , such as wafer stocker or reticle stocker .