EP0092944A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Method for packaging electronic parts
Assignee: Toshiba Corp
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Filing: 1983-04-15
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Granted: —
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Expires: 2003-04-15
Abstract
Abstract A method for hermetically packaging electronic parts (21) such as IC chips within a space defined by a multilayer substrate (2) and a cap (22) is disclosed. A welding rib (12) is formed on the printed circuit board (2) having conductor portions (4) so as to surround those conductor portions (4) over which the electronic parts (21) are to be mounted in a later step. Metal films (20) are formed by nonelectrolytic plating on the conductor portions (4). A peripheral portion (22a) of a cap (22) is placed on the welding rib (12). A laser beam is radiated onto the contact portion between the peripheral portion (22a) and the welding rib (12) so as to weld them together. At this time, a portion of the welding rib (12) which is subject to laser radiation is not covered with the maul film (20). Welding is thus performed in the absence of phosphorus, which is inevitably contained in the metal film (20) formed by nonelectrolytic plating and is a principal cause of cracking at a welded portion.
Inventors
- 👤 Yoshitaka Fukuoka
- 👤 Toshiaki Komine
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 19:13
CPC Classifications
H; H10; H10W; H10W76/00; H10W76/10; H10W76/12; H10W76/15; H10W76/157; H10W90/00; H10W95/00; H10W72/00; H10W72/851; H10W72/874; H10W72/884; H10W90/701; H10W90/731; H10W90/734; H10W90/751; H10W90/754; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49117; Y10T29/49124; Y10T29/4913; Y10T29/49144; Y10T29/49826; Y10T29/49885
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
246 words
A method for packaging electronic parts, comprising the steps of: forming a ring-shaped welding rib (12) on a multilayer substrate (2) having conductor portions (4) so as to surround those conductor portions (4) over which the electronic parts (21) are to be mounted in a later step; forming metal films (20) by nonelectrolytic plating on conductor portions (4) of the multilayer substrate (2) ; mounting the electronic parts (21) on the metal films (20) on some of the conductor portions (4); mounting a cap (22) on the welding rib (]2) such that a peripheral portion (22a) of the cap (22) is placed on the welding rib (12), the cap (22) having substantially the same outer shape as the welding rib (12); and radiating a laser beam on the contact portion between the welding rib (12) and the peripheral portion (22a) of the cap (22) and welding the welding rib (12) and the peripheral portion (22a) together, thereby hermetically sealing the electronic parts (21) within a space defined by the multilayer substrate (2) and the cap (22), wherein the metal film (20) is not formed on a portion of the welding rib (12) which is radiated with the laser beam, so that welding is performed in the absence of a phosphorus component, the phosphorus component being inevitably contained in the metal film (20) formed by nonelectrolytic plating and being a cause of cracking at the welded portion between the welding rib (12) and the peripheral portion (22a).
Claim 2
Independent Claim
246 words
A method for packaging electronic parts, comprising the steps of: forming a ring-shaped welding rib (12) on a multilayer substrate (2) having conductor portions (4) so as to surround those conductor portions (4) over which the electronic parts (21) are to be mounted in a later step; forming metal films (20) by nonelectrolytic plating on conductor portions (4) of the multilayer substrate (2) ; mounting the electronic parts (21) on the metal films (20) on some of the conductor portions (4); mounting a cap (22) on the welding rib (]2) such that a peripheral portion (22a) of the cap (22) is placed on the welding rib (12), the cap (22) having substantially the same outer shape as the welding rib (12); and radiating a laser beam on the contact portion between the welding rib (12) and the peripheral portion (22a) of the cap (22) and welding the welding rib (12) and the peripheral portion (22a) together, thereby hermetically sealing the electronic parts (21) within a space defined by the multilayer substrate (2) and the cap (22), wherein the metal film (20) is not formed on a portion of the welding rib (12) which is radiated with the laser beam, so that welding is performed in the absence of a phosphorus component, the phosphorus component being inevitably contained in the metal film (20) formed by nonelectrolytic plating and being a cause of cracking at the welded portion between the welding rib (12) and the peripheral portion (22a).
Claim 3
Dependent Claim
38 words
The method according to claim 1, characterized in that the welding rib (12) is fixed on a ring-shaped conductor pattern (14) through an adhesive layer (16), the ring-shaped conductor pattern (14) being formed on the multilayer substrate (2).
Claim 4
Dependent Claim
27 words
The method according to claim 1, characterized in that the metal film (20) is not formed at all on the top surface of the welding rib (12).
Claim 5
Independent Claim
252 words
A method for packaging electronic parts, comprising the steps of: forming a ring-shaped welding rib (12) on a multilayer substrate (2) having conductor portions so as to surround those conductor portions (4) over which the electronic parts (21) are to be mounted in a later step; forming a nonmetallic mask coating (18) on a portion of the welding rib (12) which is subjected to laser radiation in a subsequent step and which extends along the entire circumference of the welding rib (12); forming metal films (20) by nonelectrolytic plating on the exposed portion of the welding rib (12) and on the conductor portions (4); removing the mask coating (18), thereby providing a portion of the welding rib (12) which is not covered with the metal film (20); mounting the electronic parts (21) on the metal films (20) on some of the conductor portions (4); mounting a cap (22) on the welding rib (12) such that a peripheral portion (22a) of the cap (22) is placed on the portion of the welding rib (12) which is not covered with the metal film (20), the cap (22) having an outer shape substantially the same as the welding rib (12); and radiating a laser beam on the contact portion between the welding rib (12) and the peripheral portion (22a) of the cap (22) to weld the welding rib (12) and the peripheral portion (22) together, thereby hermetically sealing the electronic parts (21) within a space defined by the multilayer substrate (2) and the cap (22).
Claim 6
Independent Claim
252 words
A method for packaging electronic parts, comprising the steps of: forming a ring-shaped welding rib (12) on a multilayer substrate (2) having conductor portions so as to surround those conductor portions (4) over which the electronic parts (21) are to be mounted in a later step; forming a nonmetallic mask coating (18) on a portion of the welding rib (12) which is subjected to laser radiation in a subsequent step and which extends along the entire circumference of the welding rib (12); forming metal films (20) by nonelectrolytic plating on the exposed portion of the welding rib (12) and on the conductor portions (4); removing the mask coating (18), thereby providing a portion of the welding rib (12) which is not covered with the metal film (20); mounting the electronic parts (21) on the metal films (20) on some of the conductor portions (4); mounting a cap (22) on the welding rib (12) such that a peripheral portion (22a) of the cap (22) is placed on the portion of the welding rib (12) which is not covered with the metal film (20), the cap (22) having an outer shape substantially the same as the welding rib (12); and radiating a laser beam on the contact portion between the welding rib (12) and the peripheral portion (22a) of the cap (22) to weld the welding rib (12) and the peripheral portion (22) together, thereby hermetically sealing the electronic parts (21) within a space defined by the multilayer substrate (2) and the cap (22).
Claim 7
Dependent Claim
38 words
The method according to claim 4, characterized in that the welding rib (12) is fixed on a ring-shaped conductor pattern (14) through an adhesive layer (16), the ring-shaped conductor pattern (14) being formed on the multilayer substrate (2).
Claim 8
Dependent Claim
18 words
The method according to claim 4, characterized in that the mask coating (18) consists of a photoresist film.
Claim 9
Dependent Claim
25 words
The method according to claim 4, characterized in that the mask coating is formed to cover the entire top surface of the welding rib (12).
Claim 10
Independent Claim
239 words
A method for packaging electronic parts, comprising the steps of: forming a ring-shaped welding rib (12) on a multilayer substrate (2) having conductor portions (4) so as to surround those conductor portions (4) over which the electronic parts (21) are to be mounted in a later step; forming a metal film (20) by nonelectrolytic plating to cover the conductor portions (4) and the entire surfaces of the welding rib (12); removing a portion of the metal film (20) on the welding rib (12), which extends along the entire circumference of the welding rib (12) and which is subjected to laser radiation in a subsequent step, thereby providing an exposed portion of the welding rib (12) which is not covered with the metal film (20); mounting the electronic parts (21) on the metal films (20) on some of the conductor portions (4); mounting a cap (22) on the exposed portion of the welding rib (12) such that a peripheral portion (22a) of the cap (22) is placed on the exposed portion, the cap (22) having substantially the same outer shape as the welding rib (12); and radiating a laser beam on the contact portion between the welding rib (12) and the peripheral portion (22a) of the cap (22) to weld the welding rib (12) and the peripheral portion (22) together, thereby hermetically sealing the electronic parts (21) within a space defined by the multilayer substrate (2) and the cap (22).
Claim 11
Independent Claim
239 words
A method for packaging electronic parts, comprising the steps of: forming a ring-shaped welding rib (12) on a multilayer substrate (2) having conductor portions (4) so as to surround those conductor portions (4) over which the electronic parts (21) are to be mounted in a later step; forming a metal film (20) by nonelectrolytic plating to cover the conductor portions (4) and the entire surfaces of the welding rib (12); removing a portion of the metal film (20) on the welding rib (12), which extends along the entire circumference of the welding rib (12) and which is subjected to laser radiation in a subsequent step, thereby providing an exposed portion of the welding rib (12) which is not covered with the metal film (20); mounting the electronic parts (21) on the metal films (20) on some of the conductor portions (4); mounting a cap (22) on the exposed portion of the welding rib (12) such that a peripheral portion (22a) of the cap (22) is placed on the exposed portion, the cap (22) having substantially the same outer shape as the welding rib (12); and radiating a laser beam on the contact portion between the welding rib (12) and the peripheral portion (22a) of the cap (22) to weld the welding rib (12) and the peripheral portion (22) together, thereby hermetically sealing the electronic parts (21) within a space defined by the multilayer substrate (2) and the cap (22).
Claim 12
Dependent Claim
38 words
The method according to claim 8, characterized in that the welding rib (12) is fixed on a ring-shaped conductor pattern (14) through an adhesive layer (16), the ring-shaped conductor pattern (14) being formed on the multilayer substrate (2).
Claim 13
Dependent Claim
26 words
The method according to claim 8, characterized in that the metal film (20) formed on the top surface of the welding rib (12) is completely eliminated.
Claim 14
Dependent Claim
17 words
The method according to claim 10, characterized in that the metal film (20) is removed by grinding.
Claim 15
Dependent Claim
22 words
The method according to claim 11, characterized in that the metal film (20) is removed by being urged against a rotating grinder.
Claim 16
Dependent Claim
51 words
The method according to claim 8, characterized in that the step of removing the metal film (20) is carried out by covering with a mask coating a portion of the metal film (20) other than the portion to be removed, and etching off the exposed portion of the metal film (20).
Claim 17
Dependent Claim
17 words
The method according to claim 13, characterized in that the mask coating consists of a photoresist film.
References Cited (Backward Citations)
US3211827A
Cited
DE2326614A1
Cited
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