Method and apparatus for encapsulating semi-conductors

• US 4,900,501 A
• Filed: 10/30/1986
• Issued: 02/13/1990
• Est. Priority Date: 11/08/1985
• Status: Expired due to Term

• Current Assignee: Renesas Technology Corporation (Renesas Electronics Corporation)
• Original Assignee: Hitachi, Ltd.
• Inventors: Nakagawa, Takashi, Ozawa, Masakazu, Nishi, Kunihiko, Saeki, Junichi, Kaneda, Aizo
• Primary Examiner(s): Hoag, Willard E.
• Application Number:
  US07/924,773
• Time in Patent Office: 1,202 Days
• Field of Search: 249/83, 249/119, 249/85, 425/116, 425/117, 425/121, 425/122, 425/126 R, 425/128, 425/129 R, 264/272.14, 264/272.17, 264/299, 264/297.1-297.3, 437/206, 437/207, 437/217, 437/220, 437/224, 357/70, 361/421, 174/52.1, 174/52.2
• US Class Current: 264/272.17
• CPC Class Codes: B29C 2045/2712 Serial gates for moulding articles in successively filled serial mould cavities
• CPC Class Codes: B29C 45/14655 connected to or mounted on a carrier, e.g. lead frame
• CPC Class Codes: H01L 21/565 Moulds
• CPC Class Codes: H01L 2224/45144 Gold (Au) as principal constituent
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 24/97 the devices being connected to a common substrate, e.g. interposer, said common substrate being separable into individual assemblies after connecting
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/181 Encapsulation

Abstract

A resin-molded semiconductor is produced by using an apparatus which comprises a mold having a plurailty of pots from which a molding resin is fed under pressure, mutually independent runners extending from each pot, and a plurality of cavities serially disposed at the end of each runner, said cavities being filled with a molding resin fed under pressure from said pots, with a part to be molded placed in each cavity. The process and apparatus of this invention prevent the molding defects resulting from the excessive flow resistance of resin and greatly improves the use efficiency of resin.

Claims

1. In a method for producing resin-encapsulated semiconductors the steps comprising;

providing a mold having a plurality of pots from which a molding resin is fed under pressure, mutually independent runners extending from each pot, and a plurality of cavities serially disposed at an end of each runner, wherein a first cavity in each series located at the nearest position from a pot is connected to a runner through a gate, and each further cavity in each series is connected to each adjacent cavity in each series only through a slit formed as a flow channel in a lead frame interposed between a top part and a bottom part of said mold;

discharging said resin from said pots into said runners such that said resin is fed only to said first cavity of each series through said gate; and

discharging said resin from a cavity to an adjacent cavity only through said slit sequentially up to the last cavity in each series.

2. An apparatus for producing resin-molded semiconductors which comprises a mold having a plurality of pots from which a molding resin is fed under pressure, mutually independent runners extending from each pot, and a plurality of cavities serially disposed at the end of each runner, each of said runners being connected directly only to a first of said cavities in an associated series, a first of said cavities in each series being connected with one of said runners through a gate, and further of said cavities in each series being connectable with adjacent cavities in each series only through slits formed in a lead frame interposed between a top part and a bottom part of said mold.

3. An apparatus for producing resin-encapsulated semiconductors which comprises a mold having a plurality of pots from which a resin is fed under pressure, mutually independent runners extending from each pot, a plurality of cavities serially disposed at the end of each runner, each of said runners being connected directly only to a first of said cavities in an associated series, the mold having a top part and a bottom part, said top part and said bottom part being provided so as to hold a lead frame interposed therebetween, the top and bottom mold parts being provided such that a lead frame having a plurality of lead frame sections each associated with a chip, said lead frame sections being arranged to extend in two directions, can be held between the top and bottom mold parts.

4. A method for producing resin-encapsulated semiconductors which comprises:

providing a mold having a plurality of pots from which a molding resin is fed under pressure, mutually independent runners extending from each pot, and a plurality of cavities serially disposed at the end of each runner;

interposing a lead frame between a top part and a bottom part of said mold; and

discharging said resin from said pots into said runners to fill said cavities sequentially.

wherein said lead frame comprises a plurality of lead frame sections, each associated with a chip, said lead frame sections being arranged to extend in two directions.