Apparatus and methods to form high efficiency and uniform Fresnel lens arrays for ultrasonic liquid manipulation are provided. An ultrasonic transducer array may be fabricated by forming top and bottom electrodes on top and bottom surfaces of a sensor plate. The ultrasonic transducer array may generate ultrasonic energy to manipulate one or more samples. Each of the top and bottom electrodes may be coupled to a radio frequency source and arranged to form one of a solid shape or a pattern. Additional apparatus and methods are disclosed.