System for encapsulation of semiconductor chips

A method of encapsulating at least a portion of a semiconductor wafer having a plurality of regions which are to be exposed through the encapsulant, said method comprising the steps of

• laminating one or more sheets of dry film photoresist material onto a surface of the wafer,
• aligning a photomask with the wafer so that a predetermined light-transmitting pattern of the mask coincides with certain areas of the wafer surface,
• directing light onto the photomask and through the light-transmitting pattern of the mask onto the wafer, and
• developing the photoresist material to remove the material from over said regions of the wafer to define windows in the material through which the regions are exposed,
• wherein the semiconductor wafer includes a plurality of field-effect transistor devices, each of which includes a gate region corresponding to a different one of the regions to be exposed through the encapsulant, said method further comprising the step of applying a chemical sensitive membrane system into each of the windows defined in the photoresist material to adhere to the sides of the windows and cover the corresponding exposed regions.