An inkjet printhead includes: a rigid elongate manifold having ink supply channels extending along its length and a plurality of ink outlets defined therein; a shim attached to the manifold, the shim having a plurality of shim apertures for receiving ink from the ink outlets; and a plurality of printhead chips adhesively bonded directly to the shim, each printhead chip receiving ink from one or more of the ink outlets. The shim is formed of a metal alloy having a CTE of 5 ppm/° C. or less and includes an adhesion-promoting surface film layer.