Abstract: Apparatus suitable for processing semiconductor slices, comprises a tank (1) for receiving a jig carrying semiconductor slices, a first supply line (2) for supplying a processing liquid to the tank (1), a supply valve (3) for controlling liquid supply through the first supply line (2), the supply valve (3) being operable in response to changes in fluid pressure at a control port (4) of the supply valve (3) and a second supply line (5) for supplying fluid to the control port (4) to control operation of the supply valve (3). The second supply line (5) communicates with an inlet (8) of the tank (1) via a control valve (7) which is operable in response to changes within the tank to control the fluid pressure at the control port (4) and so control operation of the supply valve (3).In the arrangement shown in FIG. 1, a valve member (7a) of the valve (7) is carried by a platform (9) pivotally mounted within the tank (1).

Abstract: Laser printing is used to print information relating to, for example, device characteristics on the envelope of a semiconductor device. Where that envelope is of plastics material of sufficiently high purity to be acceptable as an encapsulation, the contrast of the laser printed areas can be low when compared with the unprinted areas. In a laser printable envelope in accordance with the invention an insert (5) is introduced into a plastics encapsulation (2) and the surface (7) of the insert provides a surface for the envelope which is capable of receiving laser printing at high contrast in comparison to the external surface of the encapsulation. The insert is separated from the semiconductor element 10 and connecting wires 11 by a part 12 of the encapsulation. The insert may be of laminated structure, for example Formica (Trade Mark).