Electrochemical additive manufacturing method using deposition feedback control

Patent metadata

Field	Value
Publication number	US-2023059846-A1
Application number	US-202217982338-A
Country	US
Kind code	A1
Filing date	Nov 7, 2022
Priority date	Aug 23, 2019
Publication date	Feb 23, 2023
Grant date	—

Abstract

A system and method of using electrochemical additive manufacturing to add interconnection features, such as wafer bumps or pillars, or similar structures like heatsinks, to a plate such as a silicon wafer. The plate may be coupled to a cathode, and material for the features may be deposited onto the plate by transmitting current from an anode array through an electrolyte to the cathode. Position actuators and sensors may control the position and orientation of the plate and the anode array to place features in precise positions. Use of electrochemical additive manufacturing may enable construction of features that cannot be created using current photoresist-based methods. For example, pillars may be taller and more closely spaced, with heights of 200 μm or more, diameters of 10 μm or below, and inter-pillar spacing below 20 μm. Features may also extend horizontally instead of only vertically, enabling routing of interconnections to desired locations.

First claim

What is claimed is:

1 . An electrochemical additive manufacturing method, comprising steps of:
placing a surface of a cathode into an electrolyte solution, wherein an object to be manufactured is constructed by electrochemically depositing material onto the cathode; placing an anode array in contact with the electrolyte solution, wherein:
the anode array comprises a plurality of deposition anodes; and
each of the plurality of deposition anodes is configured to provide current that flows therefrom to the cathode through the electrolyte solution, resulting in deposition of the material onto the surface of the cathode; and
manufacturing the object by transmitting control signals to the anode array so that the material deposited onto the surface of the cathode forms a rigid interconnection feature comprising a first portion, which is angled at a first angle relative to the surface of the cathode, wherein the first angle is a non-orthogonal angle.

2 . The electrochemical additive manufacturing method according to claim 1 , wherein the rigid interconnection feature comprises a second portion, which is angled at a second angle relative to the surface of the cathode, wherein the second angle is different than the first angle and a non-orthogonal angle is defined between the first portion and the second portion of the rigid interconnection feature.

3 . The electrochemical additive manufacturing method according to claim 2 , wherein the second angle is an orthogonal angle.

4 . The electrochemical additive manufacturing method according to claim 2 , wherein the non-orthogonal angle defined between the first portion and the second portion is an obtuse angle.

5 . The electrochemical additive manufacturing method according to claim 4 , wherein:
the rigid interconnection feature comprises a bend; the first portion of the rigid interconnection feature is connected to the second portion of the rigid interconnection feature by the bend; and the bend comprises a sharp curve.

6 . The electrochemical additive manufacturing method according to claim 2 , wherein an entire length of the first portion of the rigid interconnection feature is more than an entire length of the second portion of the rigid interconnection feature.

7 . The electrochemical additive manufacturing method according to claim 2 wherein the second portion of the rigid interconnection feature extends directly from the surface of the cathode.

8 . The electrochemical additive manufacturing method according to claim 2 , wherein the first portion of the rigid interconnection feature comprises and terminates at a cantilevered end.

9 . The electrochemical additive manufacturing method according to claim 2 , wherein the control signals are transmitted to the anode array so that the material deposited onto the surface of the cathode forms a plurality of interconnection features each comprising the first portion and the second portion.

10 . The electrochemical additive manufacturing method according to claim 9 , wherein a minimum distance between the second portions of adjacent ones of the plurality of interconnection features is more than a minimum distance between the first portions of the adjacent ones of the plurality of interconnection features.

11 . The electrochemical additive manufacturing method according to claim 9 , wherein:
the first portion of each one of the plurality of connection features comprises and terminates at a cantilevered end; and a first offset, in a direction parallel to the surface of the cathode, between the second portion of a first one of the plurality of connection features to the second portion of a second one of the plurality of connection features is greater than a second offset, in the direction parallel to the surface of the cathode, between the cantilevered end of the first one of the plurality of connection features and the cantilevered end of the second one of the plurality of connection features.

12 . The electrochemical additive manufacturing method according to claim 9 , wherein the first angle of a first one of the plurality of connection features is different than the first angle of a second one of the plurality of connection features.

13 . The electrochemical additive manufacturing method according to claim 9 , wherein:
a non-orthogonal angle is defined between the first portion and the second portion of each one of the plurality of connection features; and the non-orthogonal angle defined between the first portion and the second portion of a first one of the plurality of connection features is different than the non-orthogonal angle defined between the first portion and the second portion of a second one of the plurality of connection features.

14 . The electrochemical additive manufacturing method according to claim 9 , wherein:
an entire length of the first portion of a first one of the plurality of interconnection features is different than an entire length of the first portion of a second one of the plurality of interconnection features; and an entire length of the second portion of the first one of the plurality of interconnection features is different than the entire length of the second portion of the second one of the plurality of interconnection features.

15 . The electrochemical additive manufacturing method according to claim 14 , wherein:
the first one of the plurality of interconnection features is adjacent to the second one of the plurality of interconnection features; and the entire length of the first portion of the first one of the plurality of interconnection features is greater than the entire length of the first portion of the second one of the plurality of interconnection features; and the entire length of the second portion of the first one of the plurality of interconnection features is greater than the entire length of the second portion of the second one of the plurality of interconnection features.

16 . The electrochemical additive manufacturing method according to claim 15 , wherein the second angle is an orthogonal angle.

17 . The electrochemical additive manufacturing method according to claim 15 , wherein:
in a first direction, parallel to the surface of the cathode, from a point on the surface of the cathode, the first one of the plurality of interconnection features is before the second one of the plurality of interconnection features; in a second direction, parallel to the surface of the cathode and opposite the first direction, from the point on the surface of the cathode, a third one of the plurality of interconnection features is before a fourth one of the plurality of interconnection features; the entire length of the first portion of the third one of the plurality of interconnection features is greater than the entire length of the first portion of the fourth one of the plurality of interconnection features; and the entire length of the second portion of the third one of the plurality of interconnection features is greater than the entire length of the second portion of the fourth one of the plurality of interconnection features.

18 . An electrochemical additive manufacturing method, comprising steps of:
placing a semiconductor die into an electrolyte solution, wherein an object to be manufactured is constructed by electrochemically depositing material onto first connection points that correspond to connection pads on the semiconductor die; placing an anode array in contact with the electrolyte solution, wherein:
the anode array comprises a plurality of deposition anodes; and

Assignees

• Fabric8Labs Inc

Inventors

• Pain David
• Edmonds Andrew
• Herman Jeffrey
• Pateros Charles
• Shaik Kareemullah

Classifications

• H10W70/041

  Connecting or disconnecting interconnections to or from leadframes, e.g. connecting bond wires or bumps · CPC title

• H10W40/037

  Assembling together parts thereof · CPC title

• H10W72/0198

  batch processes · CPC title

• H10W72/237

  Multiple bump connectors having different shapes · CPC title

• H10W72/247

  Dispositions of multiple bumps · CPC title