Method and system for 3D alignment in wafer scale integration

A substrate bonding system comprising:

• (a) a first substrate table configured to hold a first substrate with a first orientation, the first substrate having a front surface comprising a first target portion that includes a first device, the first device having first contact pads, wherein the first substrate table comprises
• (i) a first work space surface configured to hold the first substrate,
• (ii) a first position sensor arranged to measure a first optical signal generated on a first back surface alignment marker of the first substrate, and
• (iii) a first actuator arranged to alter a first table position and the first orientation of the first substrate table;
• (b) a second substrate table configured to hold a second substrate with a second orientation, the second substrate having a second front surface comprising a second target portion that includes a second device, the second device having second contact pads, wherein the second substrate table comprises
• (i) a second work space surface configured to hold the second substrate,
• (ii) a second position sensor arranged to measure a second optical signal generated on a second back surface alignment mark of the second substrate, and
• (iii) a second actuator arranged to alter a second table position and the second orientation of the second substrate table, and
• (c) a controller,
• wherein the substrate bonding system is arranged to bond the first and second device so that a circuit is formed by the first and second device, and
• wherein the controller is arranged to:
• (i) receive a first and a second measured optical signal from the first and second position sensors respectively;
• (ii) determine from the received first and second measured optical signals the first orientation of the first substrate and the second orientation of the second substrate, and
• (iii) send a control signal to the first and second actuators so as to alter the first table position and first orientation of the first substrate table relative to the second table position and second orientation of the second substrate table so that alignment and overlap of the first contact pads of the first device and the second contact pads of the second device are achieved.