Semiconductor package using terminals formed on a conductive layer of a circuit board

• US 6,867,485 B2
• Filed: 05/24/2001
• Issued: 03/15/2005
• Est. Priority Date: 06/11/1998
• Status: Expired due to Term

• Current Assignee: SanDisk Technologies LLC (Western Digital Corporation)
• Original Assignee: SanDisk Corporation (Western Digital Corporation)
• Inventors: Wallace, Robert F.
• Primary Examiner(s): POTTER, ROY KARL
• Application Number:
  US09/866,022
• Publication Number:
  US 20010023982A1
• Time in Patent Office: 1,391 Days
• Field of Search: 257/789, 257/693, 257/679, 257/730, 257/787
• US Class Current: 257/679
• CPC Class Codes: G11C 16/04 using variable threshold transistors, e.g. FAMOS
• CPC Class Codes: G11C 29/1201 comprising I/O circuitry
• CPC Class Codes: G11C 29/48 Arrangements in static stores specially adapted for testing by means external to the store, e.g. using direct memory access [DMA] or using auxiliary access paths
• CPC Class Codes: G11C 5/04 Supports for storage elements , e.g. memory modules; Mounting or fixing of storage elements on such supports
• CPC Class Codes: G11C 5/06 Arrangements for interconnecting storage elements electrically, e.g. by wiring
• CPC Class Codes: H01L 21/565 Moulds
• CPC Class Codes: H01L 23/24 solid or gel at the normal operating temperature of the device H01L23/3135 takes precedence
• CPC Class Codes: H01L 23/3107 the device being completely enclosed
• CPC Class Codes: H01L 23/5388 for flat cards, e.g. credit cards cards per se G06K19/00
• CPC Class Codes: H01L 24/16 of an individual bump connector
• CPC Class Codes: H01L 24/32 of an individual layer connector
• CPC Class Codes: H01L 25/0655 the devices being arranged next to each other
• CPC Class Codes: H01L 2924/14 Integrated circuits
• CPC Class Codes: H01L 2924/1433 Application-specific integrated circuit [ASIC]
• CPC Class Codes: H01L 2924/19041 being a capacitor
• CPC Class Codes: H01L 2924/19105 in a side-by-side arrangement on a common die mounting substrate
• CPC Class Codes: H05K 1/0268 for electrical inspection or testing
• CPC Class Codes: H05K 1/117 Pads along the edge of rigid circuit boards, e.g. for pluggable connectors
• CPC Class Codes: H05K 2201/09127 PCB or component having an integral separable or breakable part
• CPC Class Codes: H05K 2201/10689 Leaded Integrated Circuit [IC] package, e.g. dual-in-line [DIL]
• CPC Class Codes: H05K 2201/2018 : Presence of a frame in a printed circuit or printed circuit assembly
• CPC Class Codes: H05K 3/0052 : Depaneling, i.e. dividing a panel into circuit boards; Working of the edges of circuit boards
• CPC Class Codes: H05K 3/284 : for encapsulating mounted components H05K1/185 takes precedence

Abstract

A small package is provided for a flash EEPROM memory. The small package uses terminals which are part of a bottom conductive layer of a circuit board. In this manner, the final package can be quite thin. The circuit board can be connected to the integrated circuits and passive devices and can be encapsulated in plastic or glued to a plastic cover. In this manner, a thin and relatively inexpensive package can be formed. Additionally, the circuit board can have testing connections which can be removed before forming the final package.

Claims

1. A memory card comprising:

a circuit board having an exposed rear side, a covered front side, and edges, the exposed side having a conductive layer of the circuit board exposed to form contact terminals arranged in only one row and positioned away from an edge of the circuit board, the covered side comprising at least one integrated circuit including flash memory, circuit traces, and passive components, the circuit board also having vias connecting the contacts of the exposed side with the integrated circuit and circuit traces of the covered side;

a set of circuit elements including at least one integrated circuit having a flash EEPROM and passive components; and

a one piece cover over the front side and edges of the circuit board, such that the rear side of the circuit board is exposed to form substantially all of the rear side of the memory card.

2. The memory card of claim 1 wherein the integrated circuit is encapsulated directly onto the front side of the circuit board.

3. The memory card of claim 1, wherein the cover material includes molded plastic.

4. The memory card of claim 2, wherein the circuit board is attached to the cover by epoxy.

5. The memory card of claim 1, wherein the covered side comprises at least two integrated circuits and passive devices.

6. The memory card of claim 1, wherein the thickness of the card is less than 12 mils.

7. The memory card of claim 1, wherein the size of the card is not larger than 1¼

inches long by ⅞

of an inch wide.

28. The memory card of claim 1, wherein the contact terminals have a leading edge and a trailing edge, and wherein one or more contact terminals of the row of contact terminals has a leading edge positioned ahead of the leading edge of the remainder of the row of contact terminals.

8. A memory card comprising:

a circuit board having an exposed rear side, a covered front side, and edges, the exposed side having a conductive layer of the circuit board exposed to form contact terminals arranged in only one row and positioned away from an edge of the circuit board, the covered side comprising at least one integrated circuit including flash memory, circuit traces, and passive components, the circuit board also having vias connecting the contacts of the exposed side with the integrated circuit and circuit traces of the covered side;

a one piece cover over the front side and edges of the circuit board, such that the rear side of the circuit board is exposed to form substantially all of the rear side of the memory card; and

wherein the contact terminals have a leading edge and a trailing edge, and wherein one or more contact terminals of the row of contact terminals has a leading edge positioned ahead of the leading edge of the remainder of the row of contact terminals.

9. A memory card comprising:

an exposed side consisting of;

the exposed face of a circuit board with a conductive layer exposed to form electrical contacts substantially flush with the exposed face of the circuit board, the contacts positioned away from the edge of the card; and

a covered side comprising;

a set of circuit elements including at least one integrated circuit having a flash EEPROM and passive components; and

a one piece cover encasing the covered side and edges but not the exposed side of the circuit board.

10. The memory card of claim 9, wherein the integrated circuit is encapsulated directly onto the front side of the circuit board.

11. The card of claim 9, wherein the cover is attached to the covered side of the circuit board by epoxy.

12. The card of claim 9, wherein the cover is attached to the covered side and edges of the circuit board by injection molding.

13. The card of claim 9, wherein on the exposed side of the card, the set of terminals is the only electrical component exposed.

14. The card of claim 9, wherein the circuit elements include at least two integrated circuits and passive devices.

15. A circuit board having a front side, a back side, and edges:

the back side of the circuit board exposed and having contacts, the contacts exposed flush with the back side of the circuit board and positioned away from an edge of the circuit board, the contacts being the only electrical components on the back side of the circuit board; and

the front side covered and comprising a set of circuit elements on the circuit board, the set of circuit elements comprising at least one integrated circuit having flash EEPROM, and passive components;

wherein the circuit board is a memory storage device.

16. The circuit board of claim 15, wherein the contacts are formed from a conductive layer of the circuit board.

17. The circuit board of claim 16, wherein the contacts are arranged in only one row.

18. The circuit board of claim 15, wherein the cover includes molded plastic.

19. The circuit board of claim 15, wherein the cover extends around the perimeter of the circuit board but does not cover the exposed face of the circuit board.

20. The circuit board of claim 15, wherein the contacts on the front side are connected to the set of circuit elements on the backside by vias.

21. A package comprising:

a circuit board;

contact terminals on a first side of the circuit board;

one or more integrated circuits, passive components, and circuit traces on a second side of the circuit board, one or more of the integrated circuits comprising nonvolatile memory;

wherein the first side of the circuit board forms substantially all of a first side of the package; and

packaging material surrounding the integrated circuits and passive devices,

wherein the packaging material forms the second side of the package;

wherein the package itself, without further integration, forms a memory card.

22. The package of claim 21, wherein the contact terminals of the first side of the package are spaced away from the edge of the package.

23. The package of claim 22, wherein the contact terminals are substantially flush with the first side of the package.

24. The package of claim 22, wherein the contact terminals are in one row.

25. The package of claim 24, wherein the contact terminals have a leading edge and a trailing edge, and wherein one or more contact terminals of the row of contact terminals has a leading edge positioned ahead of the leading edge of the remainder of the row of contact terminals.

26. A memory card comprising:

a circuit board having an exposed rear side, a covered front side, and edges, the exposed side having a conductive layer of the circuit board exposed to form contact terminals arranged in only one row and positioned away from a first edge of the circuit board, the covered side comprising at least one integrated circuit including flash memory, circuit traces, and passive components, the circuit board also having vias connecting the contacts of the exposed side with the integrated circuit and circuit traces of the covered side; and

a one piece cover over the front side and edges of the circuit board, such that the rear side of the circuit board is exposed to form substantially all of the rear side of the memory card,

wherein the circuit traces comprise test connections located on a portion of the circuit board that is removed after testing but before the one piece cover is affixed to the circuit board.

27. The memory card of claim 26, wherein the row of contact terminals is parallel to the first edge and positioned proximally to the first edge of the circuit board, and wherein the test connections are positioned at a second edge of the circuit board, said second edge and said test connections positioned distally from said first edge.