Electrochemical additive manufacturing method using deposition feedback control

Patent metadata

Field	Value
Publication number	US-2022084840-A1
Application number	US-202117535437-A
Country	US
Kind code	A1
Filing date	Nov 24, 2021
Priority date	Aug 23, 2019
Publication date	Mar 17, 2022
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 using deposition feedback control, comprising:
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 deposition anode of the plurality of deposition anodes is configured to provide current that flows from the deposition anode to the cathode through the electrolyte solution, resulting in deposition of the material onto the cathode;
obtaining a build plan that comprises a layer description of a layer of the object to be manufactured, wherein the layer description comprises one or more process parameter values that affect a manufacturing process for the layer; and manufacturing the layer by:
transmitting control signals to the anode array based on the layer description of the layer;
measuring one or more feedback signals;
analyzing the one or more feedback signals to produce a deposition analysis that comprises an extent to which deposition of the layer has progressed;
determining whether deposition of the layer is not complete based on the deposition analysis; and
when deposition of the layer is not complete, determining whether to modify one or more of the one or more process parameter values associated with the layer.

2 . The method of claim 1 , further comprising modifying the layer description of one or more layers of the plurality of layers before manufacturing the one or more layers.

3 . The method of claim 2 , wherein modifying the layer description comprises changing the density of the one or more layers.

4 . The method of claim 1 , wherein the one or more feedback signals comprises a map of current across the anode array.

5 . The method of claim 1 , wherein determining whether deposition of the layer is complete comprises:
calculating a number of actual deposited pixels within the layer; calculating a number of desired deposited pixels within the layer; and determining that the deposition of the layer is complete when a ratio of the number of actual deposited pixels to the number of desired deposited pixels reaches or exceeds a threshold.

6 . The method of claim 1 , wherein determining whether deposition of the layer is complete comprises:
identifying a set of actual deposited pixels within the layer; identifying a set of desired deposited pixels within the layer; and determining that the deposition of the layer is complete when a desired fraction of the set of desired deposited pixels within the layer are within a threshold distance from one or more pixels in the set of actual deposited pixels within the layer.

7 . The method of claim 1 , wherein determining whether deposition of the layer is complete comprises:
dividing the layer into components; determining whether each component of the components is complete; and determining that the deposition of the layer is complete when all of the components are complete.

8 . The method of claim 7 , wherein determining whether each component of the components is complete comprises determining whether a ratio of the number of actual deposited pixels within each component to the number of desired deposited pixels within each component reaches or exceeds the threshold.

9 . The method of claim 7 , wherein determining whether each component of the components is complete comprises:
identifying a set of actual deposited pixels within each component; identifying a set of desired deposited pixels within each component; and determining that the deposition of each component is complete when a desired fraction of the set of desired deposited pixels within each component are within a threshold distance from one or more pixels in the set of actual deposited pixels within each component.

10 . The method of claim 1 , wherein manufacturing a layer of the plurality of layers further comprises:
dividing the target map associated with the layer into regions; and alternately activating deposition anodes in the anode array associated with each region of the regions.

11 . The method of claim 1 , wherein determining whether to modify one or more of the one or more process parameter values associated with the layer comprises, for one or more deposition anodes in the anode array, calculating one or more of:
a voltage; a current; or an amount of time of activation.

12 . The method of claim 1 , wherein manufacturing the layer further comprises performing one or more maintenance actions to maintain the condition of one or more of the anode array and the electrolyte solution.

13 . The method of claim 12 , wherein the one or more maintenance actions comprises depositing material onto one or more deposition anodes to replace material that has eroded from the one or more deposition anodes.

14 . The method of claim 12 , wherein the one or more maintenance actions comprise activating one or more deposition anodes onto which a film has formed to cause removal of the film.

15 . The method of claim 12 , wherein the one or more maintenance actions comprise removal of bubbles from the electrolyte solution.

16 . The method of claim 1 , wherein the one or more feedback signals comprises a feedback signal from a timer, and wherein determining whether deposition of the layer is not complete is based on at least the feedback signal from the timer.

17 . An electrochemical additive manufacturing method using deposition feedback control, comprising:
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 deposition anode of the plurality of deposition anodes is configured to provide current that flows from the deposition anode to the cathode through the electrolyte solution, resulting in deposition of the material onto the cathode;
obtaining a build plan that comprises a layer description of a layer of the object to be manufactured, wherein the layer description comprises one or more process parameter values that affect a manufacturing process for the associated layer; and manufacturing the layer by:
calculating a map of desired current output from each deposition anode of the anode array that will generate deposition that corresponds to the layer description of the layer;
transmitting control signals to the anode array based on the layer description of the layer;
measuring one or more feedback signals;
analyzing the one or more feedback signals to produce a deposition analysis that comprises an extent to which deposition of the layer has progressed;
determining whether deposition of the layer is complete based on the deposition analysis; and
when deposition of the layer is not complete, determining whether to modify one or more of the one or more process parameter values associated with the layer.

18 . The method of claim 17 , wherein determining whether to modify one or more of the one or more process parameter values associated with the layer comprises, for one or more deposition anodes in the anode array, calculating one or more of:
a voltage; a current; and an amount of time of activation.

19 . The method of claim 17 , wherein manufacturing th

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