Masks are the detailed blueprints for any type of integrated circuit. In the late 1960s, they regularly consisted of thousands of squares, Xs, dashed lines, dotted lines, fat lines, thin lines—each color-coded and hand-drawn as small as possible, and each symbolizing a transistor or a diode or particular type of connection among the components in a circuit. Engineers had traditionally drawn their own masks, but in 1966, Fairchild had decided to teach a select group of women how to translate the engineers’ plans into mask designs.
