Moisture and/or electrically conductive remains detection for wafers after rinse / dry process
A method, device, and apparatus is provided for detecting moisture and/or electrically conductive remains on a wafer after the wafer is removed from a drying chamber of a processing tool that includes wet clean processing. Embodiments include fixing a wafer to an endeffector between a processing chamber and a FOUP, moving the wafer from the processing chamber toward the FOUP, detecting moisture and/or electrically conductive remains on the wafer, and delivering the wafer to the FOUP, if no moisture and/or electrically conductive remains are detected, or delivering the wafer to a buffer station, if moisture and/or electrically conductive remains are detected.
1. A method comprising:
fixing a wafer to an endeffector between a processing chamber and a front opening unified pod (FOUP);
moving the wafer from the processing chamber toward the FOUP;
detecting moisture and/or electrically conductive remains on the wafer by:
providing metal structures on the endeffector;
measuring resistance, capacitance, and/or inductance between the metal structures; and
comparing the measured resistance, capacitance, and/or inductance to a resistance, capacitance, and/or inductance, respectively, of a corresponding wafer having no moisture and/or electrically conductive remains on the wafer;
delivering the wafer to the FOUP, if no moisture and/or electrically conductive remains are detected, or delivering the wafer to a buffer station, if moisture and/or electrically conductive remains are detected; and
inspecting the endeffector for the presence of moisture and/or electrically conductive remains, if moisture and/or electrically conductive remains are detected on the wafer.
2. The method according to claim 1 , further comprising disabling the processing chamber, if moisture and/or electrically conductive remains are detected.
3. The method according to claim 2 , wherein the wafer comprises one wafer of a wafer lot, and the wafer lot comprises at least one unprocessed wafer, the method further comprising moving the at least one unprocessed wafer away from the processing chamber, if moisture and/or electrically conductive remains are detected on the wafer.
4. The method according to claim 1 , further comprising initiating an acoustic and/or a visual alarm, if moisture and/or electrically conductive remains are detected on the wafer.
5. The method according to claim 1 , comprising measuring the resistance of the wafer by subjecting the metal structures of the endeffector to a pulsed or constant voltage.
6. The method according to claim 1 , comprising measuring the capacity and inductance of the wafer by employing a resonance circuit including the metal structures.
7. The method according to claim 1 , wherein a reduction in resistance, capacitance, and/or inductance of the wafer from the resistance, capacitance, and/or inductance, respectively, of the corresponding wafer indicates the presence of moisture and/or electrically conductive remains on the wafer.