Patent ID: 8426767

Claim:
A method of forming a vent in a glass substrate, the method comprising: forming a defect in the glass substrate on a scribe line; directing a beam spot of a laser onto the defect and advancing the beam spot along the scribe line; and directing a cooling jet onto the defect and advancing the cooling jet along the scribe line with the beam spot to form the vent in the glass substrate, wherein a cooling spot of the cooling jet is positioned on a surface of the glass substrate such that the surface is cooled from a maximum temperature, and a change in temperature ΔT of a surface of the glass substrate due to cooling satisfies the equation: Δ ⁢ ⁢ T ≥ 2 ⁢ σ th CTE · E , where: σ th is a threshold tensile stress for forming the vent; CTE is a coefficient of thermal expansion of the glass substrate; and E is the Young's modulus of the glass substrate.