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AssigneeSharp Laboratories of America, Inc.
InventorsYasuhiro Mitani, Apostolos T. Voutsas, Mark A. Crowder
Estimating the term…
A mask with sub-resolution aperture features and a method for smoothing an annealed surface using a sub-resolution mask pattern are provided. The method comprises: supplying a laser beam having a first wavelength; supplying a mask with a first mask section having apertures with a first dimension and a second mask section with apertures having a second dimension, less than the first dimension; applying a laser beam having a first energy density to a substrate region; melting a substrate region in response to the first energy density; crystallizing the substrate region; applying a diffracted laser beam to the substrate region; and, in response to the diffracted laser beam, smoothing the substrate region surface. In some aspects of the method, applying a diffracted laser beam to the substrate area includes applying a diffracted laser beam having a second energy density, less than the first energy density, to the substrate region. The second energy density is in the range of 40% to 70% of the first energy density, and preferably in the range of 50% to 60% of the first energy density.
A method for smoothing an annealed surface using a sub-resolution mask pattern, the method comprising:
A laser annealing mask with sub-resolution aperture patterns, the mask comprising:
Dependencies are inferred from the claim text.
From the US filing history. Foreign family members aren’t listed.
Backward citations are indexed for grants only.
Elements: silicon
Single-crystal growth by zone-melting
Single-crystal growth
Term end not estimated
1. Field of the Invention
This invention generally relates to integrated circuit (IC) and liquid crystal display (LCD) fabrication and, more particularly, to a system and method for smoothing the surface of a crystallized substrate during a laser annealing process.
2. Description of the Related Art
FIG. 1 is a diagram illustrating the LILaC process (prior art).
FIG. 2 is a conventional laser annealing mask (prior art).
FIG. 3 is a pictorial representation of a system to accomplish the optical projection and the step-and repeat process (prior art).
FIG. 4 is a plan view of the present invention laser annealing mask with sub-resolution aperture patterns. The mask 400 comprises at least one section 402 with aperture patterns for transmitting approximately 100% of incident light, and at least one section 404 with aperture patterns for diffracting incident light.
FIG. 5 depicts a variation of the sub-resolution mask of FIG. 4. As shown, mask 500 comprises a plurality of adjacent 100% transmission sections 502a, 502b, and 502c with aperture patterns for transmitting approximately 100% of incident light. Also shown, the mask 500 includes a plurality of adjacent sections 504a through 504f with aperture patterns for diffracting incident light. The number of adjacent 100% transmission sections typically varies between 2 and 5 (three are shown), although the present invention is not limited to any particular number. Likewise, the number of adjacent diffracting sections typically varies between 2 and 5. Such a mask would be useful in smoothing a laser annealed surface, regardless of the direction of mask with respect to the underlying substrate.
More specifically, a first set 506 of a plurality of adjacent sections with aperture patterns for diffracting incident light is shown with a second set 508 of a plurality of adjacent sections with aperture patterns for transmitting approximately 100% of incident light, adjacent the first set 506. A third set 510 of a plurality of adjacent sections with aperture patterns for diffracting incident light is adjacent the second set 508. As mentioned above, the first and third sets 506 and 510 typically include between 2 and 6 adjacent sections. Three adjacent sections are shown in each set.