CIRCUIT BOARD, SEMICONDUCTOR DEVICE, AND METHOD OF MANUFACTURING SEMICONDUCTOR DEVICE

• US 20090090543A1
• Filed: 10/01/2008
• Published: 04/09/2009
• Est. Priority Date: 10/05/2007
• Status: Abandoned Application

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: FURUYAMA, Masaharu, MIZUTANI, Daisuke, SAKUYAMA, Seiki, AKAMATSU, Toshiya
• Application Number:
  US12/243,500
• Publication Number:
  US 20090090543A1
• Time in Patent Office: Days
• US Class Current: 174/257
• CPC Class Codes: H01L 2224/13023 the whole bump connector protruding from the surface
• CPC Class Codes: H01L 23/49811 Additional leads joined to the metallisation on the insulating substrate, e.g. pins, bumps, wires, flat leads H01L23/49827 takes precedence
• 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 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 2924/15311 being a ball array, e.g. BGA
• CPC Class Codes: H05K 2203/1105 Heating or thermal processing not related to soldering, firing, curing or laminating, e.g. for shaping the substrate or during finish plating
• CPC Class Codes: H05K 3/10 in which conductive material is applied to the insulating support in such a manner as to form the desired conductive pattern
• CPC Class Codes: H05K 3/244 Finish plating of conductors, especially of copper conductors, e.g. for pads or lands selective plating methods H05K3/243; finish plating of conductors made by printing techniques H05K3/246; solder as finish H05K3/3457, e.g. by plating H05K3/3473
• CPC Class Codes: H05K 3/3436 having an array of bottom contacts, e.g. pad grid array or ball grid array components
• CPC Class Codes: H05K 3/3463 Solder compositions in relation to features of the printed circuit board or the mounting process

Abstract

There is provided a circuit board to which a solder ball composed of a lead (Pb)-free solder is to be connected, a semiconductor device including an electrode and a solder ball composed of a lead (Pb)-free solder disposed on the electrode, and a method of manufacturing the semiconductor device, in which mounting reliability can be improved by enhancing the bonding strength (adhesion strength) between the solder ball composed of a lead (Pb)-free solder and the electrode.

Claims

1. A circuit board comprising:

a base composed of an insulating material; and

an electrode disposed on the base and connected to a solder ball composed of a lead free material, the electrode comprising;

a first layer containing copper as a main component and formed on the base;

a second layer containing nickel as a main component and formed on the first layer; and

a third layer containing an alloy of tin and nickel as a main component and formed on the second layer.

2. The circuit board according to claim 1 further comprising,

a fourth layer containing tin as a main component and formed on the third layer.

3. The circuit board according to claim 1, wherein the third layer has a thickness of 2 micrometers to 3 micrometers.

4. The circuit board according to claim 1, wherein the solder ball contains tin and copper.

5. The circuit board according to claim 4, wherein the solder ball further contains silver.

6. A semiconductor device comprising

a base;

a first electrode formed on the base; and

a solder ball composed of lead free solder and formed on the first electrode,

wherein the first electrode comprises;

a first layer containing copper as a main component;

a second layer containing nickel as a main component and formed on the first layer; and

a third layer containing an alloy of tin and nickel as a main component and formed on the second layer.

7. The semiconductor device according to claim 6, wherein the solder ball contains tin and copper.

8. The semiconductor device according to claim 7, wherein the solder ball further contains silver.

9. The semiconductor device according to claim 7, wherein an alloy of tin, nickel, and copper is formed between the solder ball and the third layer.

10. The semiconductor device according to claim 6, wherein the solder ball is connected to a circuit board.

11. The semiconductor device according to claim 10, wherein the circuit board comprises a second electrode, the second electrode comprising:

a base;

a fourth layer containing copper as a main component and formed on the base;

a fifth layer containing nickel as a main component and formed on the fourth layer; and

a sixth layer containing an alloy of tin and nickel as a main component and formed on the fifth layer.

12. A method for manufacturing a semiconductor device, the method comprising steps of:

forming a first electrode on a base; and

forming a solder ball composed of lead free solder on the first electrode,

wherein the step of forming the first electrode comprises steps of;

forming a first layer containing copper as a main component on the base;

forming a second layer containing nickel as a main component on the first layer;

forming a third layer containing tin as a main component on the second layer; and

forming a alloy layer of the second layer and the third layer by a heat treatment after the step of forming the third layer.

13. The method for manufacturing a semiconductor device according to claim 12, wherein the heat treatment is performed at a temperature, the temperature being equal to or higher than a melting point of the tin.

14. The method for manufacturing a semiconductor device according to claim 12, wherein the steps of forming the first layer and forming the second layer are performed by an electroless plating.

15. The method for manufacturing a semiconductor device according to claim 12, wherein the solder ball contains tin and copper.

16. The method for manufacturing a semiconductor device according to claim 15, wherein the solder ball further contains silver.

17. The method for manufacturing a semiconductor device according to claim 12, wherein an alloy of tin, nickel, and copper is formed between the solder ball and the first electrode by the step of the solder ball.

18. The method for manufacturing a semiconductor device according to claim 12, further comprising a step of forming a fourth layer containing gold as a main component between the steps of forming the second layer and forming the third layer.

19. The method for manufacturing a semiconductor device according to claim 12, further comprising a step of connecting the solder ball to a circuit board.

20. The method for manufacturing a semiconductor device according to claim 12, wherein the circuit board comprising:

a base; and

a second electrode formed on the base,

wherein the second electrode comprising;

a fifth layer containing copper as a main component and formed on the base;

a sixth layer containing nickel as a main component and formed on the fifth layer;

and a seventh layer containing an alloy of tin and nickel as a main component and formed on the sixth layer.