Circumscribing defects in optical devices
Methods of circumscribing defects in optical devices are described. A perimeter is formed about a defect by laser ablation, where the perimeter electrically isolates the defect. The perimeter does not have damage due to excess energy from the laser and thus does not create new electrical shorts.
1. A method of forming a laser ablation perimeter surrounding a defect in an optical device, the method comprising:
a. starting application of a laser with a laser focus at a first position, the first position located within an area that will be surrounded by the laser ablation perimeter;
b. translating the laser focus from the first position to a second position, the second position being a part of the laser ablation perimeter;
c. translating the laser focus about the defect along the laser ablation perimeter until the laser focus is proximate the second position;
d. closing the laser ablation perimeter by overlapping the laser focus at the second position; and
e. returning the laser focus to the area surrounded by the laser ablation perimeter where laser ablation is then ceased.
2. The method of claim 1 , wherein overlapping the laser focus at the second position generates an overlap in a range from about 10% to 100%.
3. The method of claim 1 , wherein overlapping the laser focus at the second position generates overlap in a range from about 25% to about 90%.
4. The method of claim 1 , wherein overlapping the laser focus at the second position generates overlap in a range from about 50% to about 90%.
5. A method of forming a laser ablation perimeter surrounding a defect in an optical device, the method comprising:
a. energizing a laser while a laser beam is shuttered;
b. allowing the laser to reach a steady state energy level;
c. applying a laser focus to a first position located within an area that will be surrounded by the laser ablation perimeter and circumscribing the defect with the laser beam by moving the laser focus along the laser ablation perimeter;
d. closing the laser ablation perimeter by overlapping the laser focus at a second position; and
e. returning the laser focus to the area surrounded by the laser ablation perimeter where the laser ablation is then ceased.
6. A method of forming a laser ablation perimeter surrounding a defect in an optical device, the method comprising:
a. starting application of a laser with a laser focus at a starting position, within an area that will be surrounded by the laser ablation perimeter; and
b. translating the laser focus from the starting position and about the defect until the laser focus crosses its own path, but not at the starting position.
7. The method of claim 6 , wherein the laser is stopped once the laser focus is translated past a crossing point.
8. A method of forming a laser ablation perimeter surrounding a defect in an optical device, the method comprising:
a. starting application of a laser with a laser focus at a first position, within an area that will be surrounded by the laser ablation perimeter;
b. translating the laser focus from the first position to a second position, the second position being a part of the laser ablation perimeter; and
c. translating the laser focus about the defect until the laser focus crosses its own path, between the first position and the second position.
9. The method of claim 8 , wherein the laser is stopped once the laser focus is translated past a crossing point.
10. The method of claim 1 , wherein the laser ablation perimeter has an average diameter of about 300 micrometers or less.
11. The method of claim 1 , wherein the laser ablation perimeter has an average diameter of about 200 micrometers or less.
12. The method of claim 1 , further comprising at least partially mitigating the defect.