INK DELIVERY ARRANGEMENT WITH CMOS DRIVEN NOZZLES
An ink delivery arrangement includes a silicon substrate that defines a plurality of ink inlet channels. A CMOS drive circuitry layer is arranged on the silicon substrate. A plurality of nozzle arrangements is positioned on the silicon substrate to be in fluid communication with respective ink inlet channels. Each nozzle arrangement includes an annular nozzle wall about a respective ink inlet channel. A nozzle roof is on the nozzle wall so that the wall and roof define a nozzle chamber, the roof being movable with respect to the wall. A nozzle rim is defined by the nozzle roof so that ink can be ejected from the nozzle chamber when the roof is moved with respect to the wall. An electrically actuated beam is fast with the substrate to receive current from the drive circuitry layer and is connected to the nozzle roof to move the nozzle roof when actuated by the current.
1 . An ink delivery arrangement that comprises
a silicon substrate that defines a plurality of ink inlet channels;
a CMOS drive circuitry layer arranged on the silicon substrate; and
a plurality of nozzle arrangements positioned on the silicon substrate to be in fluid communication with respective ink inlet channels, each nozzle arrangement comprising
an annular nozzle wall about a respective ink inlet channel;
a nozzle roof on the nozzle wall so that the wall and roof define a nozzle chamber, the roof being movable with respect to the wall;
a nozzle rim defined by the nozzle roof so that ink can be ejected from the nozzle chamber when the roof is moved with respect to the wall; and
an electrically actuated beam fast with the substrate to receive current from the drive circuitry layer and connected to the nozzle roof to move the nozzle roof when actuated by the current.
2 . An ink delivery arrangement as claimed in claim 1 , in which an ink passivation layer is arranged on the CMOS drive circuitry layer.
3 . An ink delivery arrangement as claimed in claim 1 , in which the nozzle arrangements are arranged in rows on the substrate and are staggered with respect to each other.
4 . An ink delivery arrangement as claimed in claim 1 , in which the CMOS drive circuitry layer includes silicon dioxide layers defining CMOS dielectric layers and CMOS top-level metal defining aligned electrode contact layers.
5 . An ink delivery arrangement as claimed in claim 4 , in which an ink diffusion barrier is positioned in the CMOS drive circuitry layer about the ink inlet channel.
6 . An ink delivery arrangement as claimed in claim 1 , in which a plurality of radially extending recesses are defined in the roof about the nozzle rim to contain radial ink flow as a result of ink escaping past the nozzle rim.
7 . An ink delivery arrangement as claimed in claim 1 , in which a lever arrangement is interposed between the nozzle roof and the electrically actuated beam to facilitate movement of the nozzle roof.