Microelectronic substrates having copper alloy conductive route structures

Patent metadata

Field	Value
Publication number	US-2016183361-A1
Application number	US-201414773108-A
Country	US
Kind code	A1
Filing date	Dec 9, 2014
Priority date	Dec 9, 2014
Publication date	Jun 23, 2016
Grant date	—

Abstract

Microelectronic substrates having copper alloy conductive routes to reduce warpage due to differing coefficient of thermal expansion of the components used to form the microelectronic substrates. In one embodiment, the conductive routes of the microelectronic substrate may comprise an alloy of copper and an alloying metal of tungsten, molybdenum, or a combination thereof. In another embodiment, the conductive routes of the microelectronic substrate may comprise an alloy of copper, an alloying metal of tungsten, molybdenum, or a combination thereof, and a co-deposition metal of nickel, cobalt, iron, or a combination thereof. In still another embodiment, the copper alloy conductive routes may have copper concentrations which are graded therethrough, which may enable better pattern formation during a subtractive etching process used to form the copper alloy conductive routes.

First claim

1 - 25 . (canceled)

26 . A microelectronic substrate, comprising:
at least one dielectric layer; and at least one copper alloy conductive route including a first surface abutting the dielectric layer and an opposing second surface, wherein the at least one copper alloy conductive route comprises copper and an alloying metal of tungsten, molybdenum, or a combination thereof.

27 . The microelectronic substrate of claim 26 , wherein the at least one copper alloy conductive route comprises between about 20% and 60% copper with the remainder being the alloying metal.

28 . The microelectronic substrate of claim 26 , wherein the at least one copper alloy conductive route comprises at least one graded copper alloy conductive route comprising between about 90% and 100% copper proximate one of the graded copper alloy layer first surface and the graded copper alloy layer second, and between about 0% and 10% copper proximate the other of the graded copper alloy layer first surface and the graded copper alloy layer second surface.

29 . The microelectronic substrate of claim 26 , wherein the at least one copper alloy conductive route further includes a co-deposition metal.

30 . The microelectronic substrate of claim 29 , wherein the co-deposition metal comprises nickel, cobalt, iron, or a combination thereof.

31 . The microelectronic substrate of claim 29 , wherein the at least one copper alloy conductive route comprises between about 20% and 60% copper with the remainder being the alloying metal and the co-deposition metal.

32 . The microelectronic substrate of claim 29 , wherein the at least one copper alloy conductive route comprises at least one graded copper alloy conductive route comprising between about 90% and 100% copper proximate one of the graded copper alloy layer first surface and the graded copper alloy layer second, and between about 0% and 10% copper proximate the other of the graded copper alloy layer first surface and the graded copper alloy layer second surface.

33 . The microelectronic substrate of claim 29 , wherein the at least one graded copper alloy conductive route comprises a concentration of copper proximate one of the graded copper alloy layer first surface and the graded copper alloy second surface between about 90% and 100% and the remained being the alloying metal and the co-deposition metal, wherein the co-deposition metal has a concentration between about trace levels and 10% and, proximate the other of the graded copper alloy layer first surface and the graded copper alloy layer second surface, having a concentration of copper between about 0% and 10% and the remainder being the alloying metal and the co-deposition metal, wherein the co-deposition metal has a concentration is between about trace levels and 10%.

34 . The microelectronic substrate of claim 28 , wherein the copper of the at least one graded copper alloy conductive route has a substantially linear concentration gradient.

35 . A method of fabricating a microelectronic substrate, comprising:
forming a dielectric layer having first surface; forming a metallization layer on the dielectric layer first surface; contacting the metallization layer with an electrodeposition solution; and forming copper alloy layer from the metallization layer by inducing an electrical potential between the electrodeposition solution and the dielectric layer, wherein the copper alloy layer comprises copper, an alloying metal of tungsten, molybdenum, or a combination thereof, and a co-deposition metal of nickel, cobalt, iron, or a combination thereof, and wherein the copper alloy layer has a first surface adjacent the dielectric layer and an opposing second surface.

36 . The method of claim 35 , further comprising etching the copper alloy layer to form at least one copper alloy conductive route.

37 . The method of claim 35 , wherein the forming copper alloy layer on the dielectric layer first surface by inducing an electrical potential between the electrodeposition solution and the dielectric layer comprises forming a graded copper alloy layer by varying the electrical potential between the electrodeposition solution and the dielectric layer.

38 . The method of claim 37 , wherein forming the graded copper alloy layer comprises forming the grade copper alloy layer having between about 90% and 100% copper proximate one of the graded copper alloy layer first surface and the graded copper alloy layer second, and between about 0% and 10% copper proximate the other of the graded copper alloy layer first surface and the graded copper alloy layer second surface.

39 . The method of claim 37 , wherein forming the graded copper alloy layer comprises forming the grade copper alloy layer having a concentration of copper proximate one of the graded copper alloy layer first surface and the graded copper alloy second surface between about 90% and 100% and the remainder being the alloying metal and the co-deposition metal, wherein the co-deposition metal has a concentration between about trace levels and 10% and, proximate the other of the graded copper alloy layer first surface and the graded copper alloy layer second surface, a concentration of copper between about 0% and 10% and the remainder being the alloying metal and the co-deposition metal, wherein the co-deposition metal has a concentration between about trace levels and 10%.

40 . The method of claim 37 , further comprising etching the graded copper alloy layer to form at least one graded copper alloy conductive route.

41 . The method of claims 37 , wherein the copper of the graded copper alloy layer has a substantially linear concentration gradient.

42 . A computing device, comprising:
a board; and a microelectronic component attached to the board, wherein the microelectronic component includes a microelectronic substrate that comprises at least one dielectric layer; and at least one copper alloy conductive route including a first surface abutting the dielectric layer and an opposing second surface, wherein the at least one copper alloy conductive route comprises copper and an alloying metal of tungsten, molybdenum, or a combination thereof.

43 . The computing device of claim 42 , wherein the at least one copper alloy conductive route comprises between about 20% and 60% copper with the remainder being the alloying metal.

44 . The computing device of claim 42 , wherein the at least one copper alloy conductive route comprises at least one graded copper alloy conductive route comprising between about 90% and 100% copper proximate one of the graded copper alloy layer first surface and the graded copper alloy layer second, and between about 0% and 10% copper proximate the other of the graded copper alloy layer first surface and the graded copper alloy layer second surface.

45 . The computing device of claim 42 , wherein the at least one copper alloy conductive route further comprises a co-deposition metal.

46 . The computing device of claim 45 , wherein the co-deposition metal comprises nickel, cobalt, iron, or a combination thereof.

47 . The computing device of claim 45 , wherein the at least one copper alloy conductive route comprises between about 20 to 60% copper with the remainder being the alloying metal and the co-deposition metal.

48 . The computing device of claim 45 , wherein the at least one copper alloy conductive route comprises at least one graded copper alloy conductive route comprising between about 90% a

Assignees

• Intel Corp

Inventors

• May Robert A
• Boyapati Sri Ranga Sai
• Alur Amruthavalli P
• Sobieski Daniel N

Classifications

• C22C27/04

  Alloys based on tungsten or molybdenum · CPC title

• H10W90/734

  between a chip and a stacked insulating package substrate, interposer or RDL · CPC title

• H10W90/724

  between a chip and a stacked insulating package substrate, interposer or RDL · CPC title

• H10W74/15

  on active surfaces of flip-chip devices, e.g. underfills · CPC title

• H10W72/07236

  Soldering or alloying · CPC title