A singulation method used in a process for making a plurality of image sensor packages is disclosed. Firstly, a semi-finished product including a plurality of package structures formed on a substrate is placed on a support having a plurality of cavities for receiving the package structures. Then, the semi-finished product is sawed into separate image sensor packages. During the sawing step, the air pressure in the cavities is decreased to create suction within the cavities such that the support abuts against at least a portion of the housing of each package structure with a gap between the transparent component and the support whereby the package structures are positioned precisely and clamped in place with the support during the sawing step.