Head and liquid ejecting apparatus

A head comprising:

• a channel formation substrate that is provided with a pressure generating chamber which communicates with a nozzle for ejecting a liquid;
• a piezo element that is provided on one surface side of the channel formation substrate;
• and
• a driving circuit board that is bonded to the one surface side of the channel formation substrate via an adhesive layer, and is provided with a driving circuit for driving the piezo element,
• wherein the piezo element and the driving circuit are electrically connected to each other via a bump which is provided on any one of the channel formation substrate and the driving circuit board,
• wherein a holding portion which is surrounded by the adhesive layer and holds the piezo element therein is provided between the driving circuit board and the channel formation substrate, and
• wherein the holding portion is opened to an atmosphere through an atmosphere open passage which is provided to penetrate the driving circuit board in a direction in which the driving circuit board and the channel formation substrate are stacked,
• wherein the holding portion includes a first holding portion and a second holding portion,
• wherein the first holding portion, which is surrounded by the adhesive layer and holds the piezo element therein, is provided between the driving circuit board and the channel formation substrate,
• wherein the second holding portion, which is surrounded by the adhesive layer and holds the bump therein, is provided between the driving circuit board and the channel formation substrate,
• wherein the first holding portion is opened to the atmosphere through the atmosphere open passage.