Microfluid ejection chip, ejection head and dispensing device

The invention discloses a microfluid ejection chip, an ejection head and a distribution device. A microfluidic ejection chip includes a silicon substrate having a fluid channel, an operating layer, and a fluid ejection element. The handling layer and the fluid ejection element are affixed to a device surface on the silicon substrate. The fluid channel is defined by a silicon sidewall of the silicon substrate, and the silicon sidewall and corners between the operating layer and the silicon sidewall adjacent to the fluid ejection element are covered by a permanent passivation layer to protect the silicon sidewall from exposure to acidic fluid. The permanent passivation layer remains on the silicon sidewall at the end of the etching of the silicon substrate to form a fluid channel. The operating layer is configured to provide an electrical connection of the fluid ejection element to the flexible circuit. Each of the silicon sidewall and the permanent passivation layer extends continuously around a perimeter of t