Internal support for top-shooter thermal ink-jet printhead

A "barrier reef" configuration, comprising a plurality of cays, or pillars, is provided, each pillar associated with the entrance to a firing chamber in a thermal ink-jet printhead. Each firing chamber is formed in a photopolymer layer, together with an associated barrier inlet channel that fluidically communicates with a common ink refill channel which acts as a common reservoir to the each firing chamber, in which resides a resistor element. When energized, the resistor element fires a droplet of ink toward a print medium. Over each resistor element is a nozzle, formed in an orifice plate, for firing the droplets of ink orthogonal to the resistor element. The pillars, which are positioned near the ink refill channel, serve to support the orifice plate and act as pillars between the substrate and the orifice plate, thereby avoiding any pinching effect that would otherwise occur for an unsupported region. Advantageously, the pillars are spaced apart by an amount equal to the smallest dimension of the system and are placed as close as possible to a common ink feed channel so as to keep contaminant particles outside the firing chamber and in the common ink feed channel region.