Manufacturing method of hermetically sealed container
A manufacturing method of a hermetic container includes steps of bonding a frame member to a first substrate, by pressing the first substrate and the second substrate to each other by an electrostatic force generated between a first electrode and a second electrode by applying a potential difference between the first electrode and the second electrode, and softening and melting the bonding material. Additional steps include cooling and solidifying the bonding material by simultaneously heating the bonding material with a local heating unit and moving the local heating unit, and increasing the potential difference between the first electrode and a segment of the second electrode, which is in a position at which the segment is heated by the local heating unit.
1. A manufacturing method of a hermetic container having first and second dielectric substrates comprising:
a step of providing a first electrode operating also as a bonding material on one of the first and second substrates, while providing a second electrode divided into a plurality of segments for simultaneously applying thereto potentials different from each other on the other of the first and second substrates;
a step of arranging the first and second substrates, so that the first and second electrodes are opposed to each other; and
a first bonding step of heating the first electrode while pressing the first and second substrates to each other to bond the first and second substrates together, wherein
the first bonding step includes steps of:
pressing the first and second substrates to each other by an electrostatic force generated between the first and second electrodes by applying a potential difference between the first and second electrodes;
softening and melting the first electrode, and then cooling and solidifying the first electrode, by simultaneously forming a locally-heated spot in the bonding material and moving the locally-heated spot relatively against the bonding material; and
increasing the potential difference between the first electrode and the segment of the second electrode at which the locally-heated spot is positioned correspondingly to the moving of the locally-heated spot.
2. The method according to claim 1 , wherein
the first electrode is formed in a continuous and closed annular shape.
3. The method according to claim 1 , wherein,
the bonding material is a frit glass.
4. The method according to claim 1 , wherein
the bonding material contains metal including any one or more of Al, Al—Si compound, Sn and In.
5. The method according to claim 1 , wherein
the heating unit is a laser light generating apparatus for emitting a laser light,
the first or second electrode is a translucent electrode, and
the laser light is irradiated through the translucent electrode to the bonding material.
6. The method according to claim 1 , wherein
the potential difference between the first electrode and the segment of the second electrode which is heated by the heating unit is decreased after cooling and solidifying the bonding material.
7. The method according to claim 1 , wherein,
during the first bonding step,
the potential difference between the first electrode and the segment of the second electrode which is heated by the heating unit is increased into a maximum value, and is maintained at the maximum value for a predetermined period,
during increasing the potential difference into the maximum value, a current charging a capacitor formed by the first and second electrodes is detected, and, in response to a detection of increasing the current, the maximum potential difference is set to be decreased, while, in response to a detection of decreasing the current, the maximum potential difference is set to be increased.
8. The method according to claim 1 , wherein,
during the first bonding step,
the potential difference between the first electrode and the segment of the second electrode which is heated by the heating unit is increased into a maximum value, is maintained at the maximum value, and is decreased thereafter,
when the potential difference is at the maximum value, the current charging the capacitor formed by the first and second electrodes is detected, and, in response to a detection of increasing the current, the potential difference is decreased.
9. The method according to claim 1 , wherein
the second substrate is a frame member, or an integrated member provided with a frame member arranged at a periphery of a flat substrate.
10. The method according to claim 9 , further comprising
a second bonding step for bonding the frame member at the periphery of the flat substrate, to form the integrated member of the flat substrate and the frame member.
11. The method according to claim 10 , wherein
the first substrate and the frame member are formed from alkali-free glass, or high strain point glass.
12. A manufacturing method of a hermetic container having first and second dielectric substrates comprising:
a step of providing a first electrode and a second electrode operating also as a bonding material and divided into a plurality of segments for simultaneously applying thereto potentials different from each other on the other of the first and second substrates, to form a gap between the first and second electrodes, on one of the first and second substrates, while providing;
a step of arranging the first and second substrates, so that the first and second electrodes are opposed to the second substrate; and
a first bonding step of heating the first electrode while pressing the first and second substrates to each other to bond the first and second substrates together, wherein
the first bonding step includes steps of:
pressing the first and second substrates to each other by an electrostatic force generated between the first and second electrodes by applying a potential difference between the first and second electrodes;
softening and melting the first electrode, and then cooling and solidifying the first electrode, by simultaneously forming a locally-heated spot in the bonding material and moving the locally-heated spot relatively against the bonding material; and
increasing the potential difference between the first electrode and the segment of the second electrode at which the locally-heated spot is positioned correspondingly to the moving of the locally-heated spot.
13. The method according to claim 12 , wherein,
between the first and second electrodes, an alternating wave transitioning between positive and negative potentials is provided.
14. The method according to claim 12 , wherein
the first electrode is formed in a continuous and closed annular shape.
15. The method according to claim 12 , wherein,
the bonding material is a frit glass.
16. The method according to claim 12 , wherein
the bonding material contains metal including any one or more of Al, Al—Si compound, Sn and In.
17. The method according to claim 12 , wherein
the second substrate is a frame member, or an integrated member provided with a frame member arranged at a periphery of a flat substrate.
18. The method according to claim 12 , wherein
the heating unit is a laser light generating apparatus for emitting a laser light,
the first or second electrode is a translucent electrode, and
the laser light is irradiated through the translucent electrode to the bonding material.
19. The method according to claim 12 , wherein
the potential difference between the first electrode and the segment of the second electrode which is heated by the heating unit is decreased after cooling and solidifying the bonding material.
20. The method according to claim 12 , wherein
the first and second electrodes are placed on the same plane, and the second electrode is placed outside of the first electrode.
21. The method according to claim 20 , wherein
the first electrode has bridges each grounded and extending between segments of the second electrode.