Flanged tube for vacuum insulated glass (vig) unit evacuation and hermetic sealing, vig unit including flanged tube, and associated methods

A method of making a vacuum insulating glass (VIG) unit subassembly, the method comprising:

• providing a first glass substrate, the first substrate including a hole formed therein, the hole being formed to have first and second portions, the first portion being closer to an outer surface of the first substrate than the second portion, the first portion having a first width across the first substrate and the second portion having a second width across the first substrate, the first width being wider than the second width, the first and second portions together forming a through-hole through the first substrate;
• and
• forwarding the first substrate to another party to:
• place in the hole a flanged pump-out tube including a skirt intermediate upper and lower portions such that the lower portion of the tube extends into the second portion and the upper portion of the tube is located in the first portion;
• seal together the first glass substrate with a second substrates in connection with an edge seal provided around peripheral edges of the first and/or second substrates, a cavity being defined by the first and second substrates, and a plurality of spacers being provided between the first and second substrates in the cavity and helping to maintain the first and second substrates in substantially parallel, spaced-apart relation to one another;
• evacuate the cavity to a pressure less than atmospheric;
• and
• laser heat the pump-out tube so as to cause at least a part of the upper portion of the tube to collapse inwardly upon itself, covering the second width and hermetically sealing the VIG unit and forming a sealed tube, the sealed tube being flush with, or partially recessed with respect to, an outermost surface of the first substrate.