Techniques for layer fencing to improve edge linearity
An ink jet process is used to deposit a material layer to a desired thickness. Layout data is converted to per-cell grayscale values, each representing ink volume to be locally delivered. The grayscale values are used to generate a halftone pattern to deliver variable ink volume (and thickness) to the substrate. The halftoning provides for a relatively continuous layer (e.g., without unintended gaps or holes) while providing for variable volume and, thus, contributes to variable ink/material buildup to achieve desired thickness. The ink is jetted as liquid or aerosol that suspends material used to form the material layer, for example, an organic material used to form an encapsulation layer for a flat panel device. The deposited layer is then cured or otherwise finished to complete the process.
1. A method of fabricating a layer of an electronic device, wherein the layer is to span an area, the area having at least one lateral edge, the method comprising:
using an ink jet printer to deposit droplets of liquid, the droplets to coalesce to form a continuous liquid coat within the area; and
using a curing mechanism to cure the continuous liquid coat to form the layer;
wherein using the ink jet printer to deposit the droplets of liquid comprises deposing droplets at a first droplet density at the at least one lateral edge to form a frame for the layer, and
depositing droplets within the frame at a second droplet density different from the first droplet density, wherein depositing droplets at the first droplet density comprises firing droplets at locations corresponding to nodes of a print grid, wherein depositing droplets at the second droplet density also comprises firing droplets at locations corresponding to nodes of the print grid, and wherein the first droplet density corresponds to droplet density at a minimum pitch relative to positional overlap between the nodes of the print grid and the at least one lateral edge.
2. The method of claim 1 , wherein depositing droplets at the first droplet density comprises depositing the droplets in a manner that defines at least one straight line.
3. A method of fabricating a layer of an electronic device, wherein the layer is to span an area, the area having at least one lateral edge, the method comprising:
using an ink jet printer to deposit droplets of liquid, the droplets to coalesce to form a continuous liquid coat within the area; and
using a curing mechanism to cure the continuous liquid coat to form the layer;
wherein using the ink jet printer to deposit the droplets of liquid comprises deposing droplets at a first droplet density at the at least one lateral edge to form a frame for the layer, and
depositing droplets within the frame at a second droplet density different from the first droplet density, wherein the depositing of droplets within the frame at the second droplet density is performed at a first region within the frame, and the method further comprises depositing droplets within the frame at a third droplet density different from the second droplet density at a second region within the frame, the second region intermediate to the first region and an edge of the at least one lateral edge.
4. The method of claim 3 , wherein the method further comprises adjusting the second droplet density according to a predetermined algorithm to obtain the third droplet density.