Abstract: A flow chamber having an upper chamber, a lower chamber, and an actuator is described. The upper chamber includes a top wall. The actuator is located distally from the top wall. The lower chamber includes a bottom wall and a sidewall. The lower chamber receives a fluid from the upper chamber when the actuator is activated. The bottom wall has orifices and at least one cavity therein. The orifices are vertically aligned with a portion of the actuator and allow the fluid to exit the lower chamber. The at least one cavity is proximate to the sidewall and distally located from the orifices.

Abstract: A flow chamber having an upper chamber, a lower chamber, and an actuator is described. The upper chamber includes a top wall. The actuator is located distally from the top wall. The lower chamber includes a bottom wall and a sidewall. The lower chamber receives a fluid from the upper chamber when the actuator is activated. The bottom wall has orifices and at least one cavity therein. The orifices are vertically aligned with a portion of the actuator and allow the fluid to exit the lower chamber. The at least one cavity is proximate to the sidewall and distally located from the orifices.

Abstract: A flow chamber having an upper chamber, a lower chamber, and an actuator is described. The upper chamber includes a top wall. The actuator is located distally from the top wall. The lower chamber includes a bottom wall and a sidewall. The lower chamber receives a fluid from the upper chamber when the actuator is activated. The bottom wall has orifices and at least one cavity therein. The orifices are vertically aligned with a portion of the actuator and allow the fluid to exit the lower chamber. The at least one cavity is proximate to the sidewall and distally located from the orifices.

Abstract: A method of making a microelectromechanical system (MEMS) device is disclosed. The method includes forming a stationary layer over a substrate. A sacrificial layer is formed over the stationary layer. The sacrificial layer is formed of a first material. A mechanical layer is formed over the sacrificial layer. A hard mask layer is formed over the mechanical layer. The hard mask layer is formed of a second material. The first and second materials are etchable by a single etchant which is substantially selective for etching the first and second materials relative to the mechanical layer. The hard mask layer is patterned after forming the hard mask layer. Subsequently, the mechanical layer is etched through the patterned hard mask layer. The patterned hard mask layer is removed simultaneously with the sacrificial layer after etching the mechanical layer.

Abstract: A method of making a microelectromechanical system (MEMS) device is disclosed. The method includes forming a stationary layer over a substrate. A sacrificial layer is formed over the stationary layer. The sacrificial layer is formed of a first material. A mechanical layer is formed over the sacrificial layer. A hard mask layer is formed over the mechanical layer. The hard mask layer is formed of a second material. The first and second materials are etchable by a single etchant which is substantially selective for etching the first and second materials relative to the mechanical layer. The hard mask layer is patterned after forming the hard mask layer. Subsequently, the mechanical layer is etched through the patterned hard mask layer. The patterned hard mask layer is removed simultaneously with the sacrificial layer after etching the mechanical layer.

Abstract: A method of making a microelectromechanical system (MEMS) device is disclosed. The method includes forming a stationary layer and a moving layer spaced from the stationary layer. The method also includes forming at least one support structure configured to support the moving layer. Forming the at least one support structure includes forming a photoresist layer over the stationary layer and patterning the photoresist layer. Patterning the photoresist layer includes exposing the photoresist layer to light through a photomask. Then, the photoresist layer is first developed with a first developing solution for a first predetermined period of time after exposing. The first developing solution is removed after first developing. Subsequently, the photoresist layer is developed a second time with a second developing solution for a second predetermined period of time after removing the first developing solution. The second developing solution is removed after the second developing process.