A dispenser, which is capable of dispensing viscous material on a substrate having a top surface and a bottom surface, includes a frame, a gantry system, and a dispensing unit. The gantry system is configured to move the dispensing unit in x-axis, y-axis, and z-axis directions. The dispenser further includes a substrate support assembly configured to support the substrate in a dispense position to dispense material on the top surface of the substrate and on the bottom surface of the substrate. The substrate support assembly includes a clamping system and an inverter system. The inverter system is configured to rotate the clamping system about an axis that is parallel to the y-axis direction between a first position in which the top surface of the substrate is in the dispense position and a second position in which the bottom surface of the substrate is in the dispense position.