The clean room in Newport, south Wales, is the size of a football field, but in the industry they call it a ballroom. Workers in full bodysuits move silicon wafers from one end to another in a series of careful steps. The 20cm slices of silicon are rigorously cleaned in chemical baths before light is used to draw precise patterns that are then etched out. It all takes place in an orange gloom to prevent light-sensitive chemicals from reacting. After robots and people test for defects, the owner Nexperia ships…