that senses the presence of an ic device by sensing a pressure drop as the quill approaches the surface of the ic device incremental movement of the quill toward the ic device during sensing may be controlled by a linear stepper motor for high precision the pick and place mechanism 140 may also include transfer mechanism 144 transfer mechanism 144 is configured to transfer ic devices 40 to the second processing station 300 as the ic devices 40 are picked from a stack processing tray 10 the transfer mechanism 144 may be a robotic arm as is shown schematically in fig4 or any other suitable device as is known in the art those of ordinary skill in the art will understand that a tray based handling system 100 may include multiple pick and place mechanisms 140 enabling the tray based handling system 100 to simultaneously remove ic devices 40 from multiple cells 30 of a stack processing tray 10 and to simultaneously transfer multiple ic devices 40 to the second processing station 300 the alignment mechanism 160 is configured to accurately align an individual cell 30 of a stack processing tray 10 resting within the target zone 165 with the extraction head 142 such that the ic devices 40 within that cell 30 may be picked from the cell 30 and transferred to the second processing station 300 generally the alignment mechanism 160 is any multi dimensional motion system capable of movement in at least two mutually perpendicular horizontal directions relative to the pick and place mechanism 140 for example as shown in fig4 the alignment mechanism 160 may be a two dimensional motion stage having a first stage 162 capable of movement in a first direction 168 and a second stage 163 capable of movement in a second perpendicular.