the present application relates to the manufacture of wafer level chip scale packages , which are a type of csp in which the traditional wire bonding arrangements are dispensed with in favour of making direct contact by means of conductive bumps to the integrated circuitry . wlcsps differ from fine pitch ball grid array and leadframe based chip scale packages in that most of the packaging process steps are performed at wafer level . a package and method of manufacture are provided which prevent the ingress of light to the internal circuitry of wlcsp packages by providing a substantially opaque coating on the inactive side of the wlcsp packages and at least partially on the sides of wlcsp packages .