A carrier cassette for wafers comprises two side plates facing each other in a first direction, each of which comprises a locking groove on an upper side of the same, at least one lower retaining rod mounted between the two opposing side plates, and at least two lateral retaining rods facing each other in a second direction, mounted between the two opposing side plates, and an upper locking rod that can be locked in the locking grooves of the opposing side plates to hold down wafers in the carrier cassette. The upper locking rod is configured to hold down the two rows of wafers and comprises projections configured to separate wafers of both rows adjacent in the first direction from each other when the upper locking rod is locked in the locking grooves.