Methods and apparatus of packaging of semiconductor devices

Patent metadata

Field	Value
Publication number	US-9349665-B2
Application number	US-201313745366-A
Country	US
Kind code	B2
Filing date	Jan 18, 2013
Priority date	Jan 18, 2013
Publication date	May 24, 2016
Grant date	May 24, 2016

Abstract

Methods and apparatuses for forming an under-bump metallization (UBM) pad above a dielectric layer are disclosed. The dielectric layer may be above a metal layer and comprises a first opening and a second opening surrounding the first opening, which divide the dielectric layer into a first area and a second area. An UBM pad extends into and fills the first opening of the dielectric layer, above the first area between the first opening and the second opening, and may further extends down at least partly into the second opening covering a part or the whole of the second opening of the dielectric layer. The UBM pad may further extend over a part of the second area of the dielectric layer if the UBM pad fills the whole of the second opening of the dielectric layer. A solder ball may be mounted on the UBM pad.

First claim

What is claimed is:

1. A device, comprising:
a substrate;
a metal layer on the substrate;
a passivation layer above the metal layer with a passivation layer opening formed therein exposing the metal layer, the passivation layer opening having sidewalls;
a dielectric layer above the passivation layer and the metal layer, the dielectric layer extending into the passivation layer opening and along the sidewalls, wherein the dielectric layer has a first opening exposing the metal layer and a ring-opening structure surrounding the first opening, the ring-opening structure comprising a second opening, a bottom surface of the second opening being a dielectric surface, a first area of the dielectric layer being between the first opening and the second opening, and a second area of the dielectric layer being outside the ring-opening structure;
an under-bump metallization (UBM) pad disposed at least partially in the first opening of the dielectric layer in contact with the metal layer, extending above the first area of the dielectric layer, and the UBM disposed in the second opening of the dielectric layer and in contact with the passivation layer, the UBM pad not contacting a sidewall of the second opening that is laterally distal to the first opening, the UBM pad not completely filling the second opening; and
a solder connector on the UBM pad, the solder connector not extending into the second opening.

2. The device of claim 1 , wherein the dielectric layer is a polymer layer, an oxide layer, or a nitride layer.

3. The device of claim 1 , wherein the ring-opening structure of the dielectric layer comprises a plurality of individual openings disconnected from each other.

4. The device of claim 1 , wherein the first area of the dielectric layer is of an annular shape.

5. The device of claim 1 , wherein the dielectric layer comprises a material selected from a group consisting essentially of an epoxy, a polyimide, a benzocyclobutene (BCB), a polybenzoxazole (PBO), or combinations thereof.

6. The device of claim 1 , wherein the first opening of the dielectric layer is of a shape selected from a group consisting essentially of a circle, a rectangle, a square, an octagon, a hexagon, an oval, or a diamond shape.

7. The device of claim 1 , wherein the second opening of the dielectric layer is an annular opening of a shape selected from a group consisting essentially of a circle, a rectangle, a square, an octagon, a hexagon, an oval, or a diamond shape.

8. The device of claim 1 , wherein the first opening has a diameter size from about 25 μm to about 35 μm.

9. The device of claim 1 , wherein the UBM pad comprises a plurality of layers made of titanium (Ti), tantalum (Ta), tantalum nitride (TaN), nickel (Ni), or copper (Cu).

10. The device of claim 1 , wherein the UBM pad comprises a U-shaped first part filling in and covering the first opening of the dielectric layer, a second part partially filling the second opening of the dielectric layer, and a third part covering the first area of the dielectric layer and connecting the first part and the second part of the UBM pad.

11. The device of claim 1 , wherein the UBM pad is of a length from about 50 μm to about 90 μm.

12. The device of claim 1 , wherein the metal layer is a contact pad or a redistribution layer (RDL).

13. A method of forming a device, comprising:
providing a substrate with a contact pad;
forming a passivation layer above the contact pad, the passivation layer having a passivation layer opening formed therein;
forming a dielectric layer above the contact pad and the passivation layer;
forming a first opening in the dielectric layer coinciding with the passivation layer opening thereby exposing the contact pad;
forming a second opening in the dielectric layer, the second opening being in a ring-opening structure that surrounds the first opening, wherein the first opening and the second opening divide the dielectric layer into a first area between the first opening and the second opening, and a second area outside the second opening;
forming an under-bump metallization (UBM) pad above the dielectric layer, wherein the UBM pad is disposed in the first opening of the dielectric layer in contact with the contact pad, extends above the first area of the dielectric layer, is disposed in the second opening of the dielectric layer in contact with the passivation layer, the UBM pad not contacting a sidewall of the second opening that is laterally distal to the first opening; and
connector.

14. The method of claim 13 , wherein the UBM pad fills the second opening of the dielectric layer, and further extends above a part of the second area of the dielectric layer.

15. The method of claim 13 , wherein the dielectric layer is a polymer layer, an oxide layer, or a nitride layer.

16. The method of claim 13 , wherein the forming the second opening comprises forming a plurality of individual openings disconnected from each other, the plurality of individual openings being in the ring-opening structure that surrounds the first opening.

17. A device, comprising:
a substrate;
a metal layer on the substrate;
a passivation layer above the metal layer with a first opening to the metal layer;
a dielectric layer above the passivation layer and the metal layer, wherein the dielectric layer comprises a second opening and a continuous-annular opening, the first opening being to the metal layer, the continuous-annular opening being to and not extending through the passivation layer, the continuous-annular opening surrounding the second opening, a first area of the dielectric layer being between the second opening and the continuous-annular opening, and a second area of the dielectric layer being outside the continuous-annular opening;
an under-bump metallization (UBM) pad disposed at least partially in the second opening of the dielectric layer in contact with the metal layer, extending above the first area of the dielectric layer, and the UBM pad disposed in the continuous-annular opening of the dielectric layer and in contact with the passivation layer, the UBM pad having a peripheral surface extending from a position directly above the first area of the dielectric layer to a lateral periphery of the UBM pad, the peripheral surface being a planar surface, the UBM pad not contacting a sidewall of the continuous-annular opening that is laterally distal from the second opening; and
a solder connector on the UBM pad, the solder connector not extending into the second opening.

18. The device of claim 17 , wherein the second opening of the dielectric layer is of a shape selected from a group consisting essentially of a circle, a rectangle, a square, an octagon, a hexagon, an oval, or a diamond shape.

19. The device of claim 17 , wherein the continuous-annular opening of the dielectric layer is an annular opening of a shape selected from a group consisting essentially of a circle, a rectangle, a square, an octagon, a hexagon, an oval, or a diamond shape.

20. A device, comprising:
a substrate;
a metal layer on the substrate;
a passivation layer on the metal layer with an opening formed therein;
a dielectric layer above the passivation layer, wherein the dielectric layer comprises a first opening coinciding with the opening in the passivation layer and a ring-opening structure, the first opening exposing the metal layer, the ring-opening structure comprising a second opening the ring-opening structure surrounding the first opening, a first area of the dielectric layer being between the fir

Assignees

• Taiwan Semiconductor Mfg

Inventors

• Chen Hsien-Wei
• Yu Tsung-Yuan
• Chen Jie
• Chen Ying-Ju

Classifications

• H10W72/29

  Bond pads specially adapted therefor · CPC title

• H10W20/49

  Adaptable interconnections, e.g. fuses or antifuses · CPC title

• H10W90/701

  characterised by the relative positions of pads or connectors relative to package parts · CPC title

• H10W72/90

  Bond pads, in general · CPC title

• H10W72/20

  Bump connectors, e.g. solder bumps or copper pillars; Dummy bumps; Thermal bumps · CPC title