Guided transport path correction
A printer deposits material onto a substrate as part of a manufacturing process for an electronic product; at least one transported component experiences error, which affects the deposition. This error is mitigated using transducers that equalize position of the component, e.g., to provide an “ideal” conveyance path, thereby permitting precise droplet placement notwithstanding the error. In one embodiment, an optical guide (e.g., using a laser) is used to define a desired path; sensors mounted to the component dynamically detect deviation from this path, with this deviation then being used to drive the transducers to immediately counteract the deviation. This error correction scheme can be applied to correct for more than type of transport error, for example, to correct for error in a substrate transport path, a printhead transport path and/or split-axis transport non-orthogonality.
1. A method of fabricating a thin-film layer, the method comprising:
controlling a conveyance system to provide relative transport between a material source and a substrate along a conveyance path, wherein during the relative transport, the substrate is to be supported by a support structure and the material source is to deposit a material onto the substrate in order to form the thin-film layer;
providing an optical source to form an optical beam and providing an optical detector located at a fixed displacement from at least one of the material source or the substrate;
causing the optical detector to detect divergence of the position of the optical detector from the optical beam during the relative transport, and responsively generate an output; and
driving at least one transducer to displace at least one of the material source or the detector relative to the conveyance path, in dependence on the output, so as to cause the position of the optical detector to remain coincident with the beam during the relative transport.
2. The method of claim 1 , wherein the method further comprises forming an electronic product from the substrate, the electronic product comprising the thin-film layer.
3. The method of claim 1 , wherein the conveyance system comprises a gripper that is to selectively engage the substrate and transport the substrate along the conveyance path, and wherein the method further comprises driving the at least one transducer during the relative transport so as to cause the substrate to travel a straight line relative to the optical beam for at least a portion of the conveyance path.
4. The method of claim 3 , wherein the material source comprises a printhead, wherein the method further comprises causing the printhead is to deposit a liquid ink onto the substrate, the material to be supplied to the substrate by the liquid ink and comprising a film-forming substance, and wherein the method further comprises processing the liquid ink following deposition onto the substrate so as to solidify the film-forming substance relative to the liquid ink, to form the thin-film layer, using at least one of a (1) a radiation source to cure the film-forming substance to form the thin-film layer, or a (2) a heat source to evaporate solvent from the liquid ink to cause the film-forming substance to form the thin-film layer.
5. The method of claim 2 , wherein the optical source is a laser and the optical beam is a laser beam oriented in a manner parallel to the conveyance path, and wherein the method further comprises using the laser beam as a virtual guide, and driving the at least one transducer so as to correct for deviation between the virtual guide and the conveyance path.
6. The method of claim 1 , wherein:
the support structure comprises a floatation table;
the method further comprises using the floatation table to provide a gas cushion;
the conveyance system comprises a vacuum gripper that is to use a vacuum to selectively engage the substrate; and
the method further comprises selectively engaging the substrate with the vacuum gripper and pulling the substrate along the conveyance path atop the gas cushion with the vacuum gripper during the relative transport.
7. The method of claim 6 , wherein the at least one transducer comprises a voice coil having a linear throw which is oriented in a direction independent to a direction of the optical beam.
8. The method of claim 7 , wherein the direction of the linear throw is normal to a surface of the substrate, and wherein the method further comprises using the linear throw to adjust a height of the substrate relative to the support structure.
9. The method of claim 7 , wherein the direction of the linear throw is parallel to the surface of the substrate, and wherein the method further comprises using the linear throw to adjust a distance between the substrate and the transport path.
10. The method of claim 7 , wherein:
the conveyance system comprises a track;
the gripper comprises a first part, which travels along the track, and a second part, which mounts the optical detector and the vacuum gripper;
the voice coil couples the first part with the second part; and
the gripper further comprises a mechanical linkage between the first part and the second part; and the method further comprises advancing the first part along the track during the relative transport, and using the mechanical linkage to constrain the second part to travel with the first part in a direction of the conveyance path during the travel of the first part along the track, while permitting the displacement of the second part relative to the first part by the voice coil, toward and away from the track.
11. The method of claim 1 , wherein the substrate is a first substrate and the method is to fabricate the thin-film layer on each given substrate of a series of substrates, including the first substrate, wherein each given substrate of the series of substrates features at least one fiducial, and wherein the method further comprises:
using a camera to image the fiducial of each given substrate of the series of substrates, including the first substrate;
mechanically positioning each given substrate of the series of substrates relative to the conveyance path, so as to align each given substrate of the series of substrates relative to the conveyance path; and
causing the vacuum gripper to engage each given substrate of the series of substrates for the relative transport following the alignment of the given substrate of the series of substrates relative to the conveyance path.
12. The method of claim 1 , wherein the at least one transducer comprises two transducers, each having a linear throw that is parallel to a surface of the substrate, and wherein the method further comprises driving the two transducers in common-mode to displace the substrate in a direction perpendicular to the conveyance path and in differential-mode to rotate the substrate relative to the conveyance path.
13. The method of claim 1 , wherein the at least one transducer comprises a piezoelectric transducer.
14. The method of claim 1 , wherein the conveyance path is characterized by mechanical imperfections, and wherein the method further comprises using optical beam, the optical detector and the at least one transducer to cause the relative transport to follow a straight line notwithstanding the mechanical imperfections.