Lam Research Corporation

Novellus Systems Incorporated

Lee Peng Chua

Steven T Mayer

Thomas Anand Ponnuswamy

Bryan L Buckalew

Robert Rash

Aaron Berke

Gabriel Hay Graham

Santosh Kumar

David W Porter

Chad Michael Hosack

Gregory Kearns

Burhanuddin Kagajwala

James Isaac Fortner

Brian Paul Blackman

Jacob Kurtis Blickensderfer

Stephen J Banik, Ii

Jacob Lee Hiester

Mark L Rea

Christopher Gage

Defu Liang

Boon Kang Ong

Systems and methods are provided for method for etch assisted gold (Au) through silicon mask plating (EAG-TSM). An example method comprises providing a seed layer on a substrate and providing a silicon mask on at least a portion of the seed layer on the substrate. The silicon mask includes one or more via to be filled with Au. The masked substrate is subjected to at least one processing cycle, each processing cycle including an Au plating sub-step and an etch treatment sub-step. The cycles are repeated until a selected via fill thickness is achieved.

Gold through silicon mask plating

Undesired deposition of metals on a lipseal (lipseal plate-out) during electrodeposition of metals on semiconductor substrates is minimized or eliminated by minimizing or eliminating ionic current directed at a lipseal. For example, electrodeposition can be conducted such as to avoid contact of a lipseal with a cathodically biased conductive material on the semiconductor substrate during the course of electroplating. This can be accomplished by shielding a small selected zone proximate the lipseal to suppress electrodeposition of metal proximate the lipseal, and to avoid contact of metal with a lipseal. In some embodiments shielding is accomplished by sequentially using lipseals of different inner diameters during electroplating of metals into through-resist features, where a lipseal having a smaller diameter is used during a first electroplating step and serves as a shield blocking electrodeposition in a selected zone. In a second electroplating step, a lipseal of a larger inner diameter is used.

Wafer shielding for prevention of lipseal plate-out

The embodiments herein relate to apparatuses and methods for electroplating one or more materials onto a substrate. Embodiments herein utilize a cross flow conduit in the electroplating cell to divert flow of fluid from a region between a substrate and a channeled ionically resistive plate positioned near the substrate down to a level lower than level of fluid in a fluid containment unit for collecting overflow fluid from the plating system for recirculation. The cross flow conduit can include channels cut into components of the plating cell to allow diverted flow, or can include an attachable diversion device mountable to an existing plating cell to divert flow downwards to the fluid containment unit. Embodiments also include a flow restrictor which may be a plate or a pressure relief valve for modulating flow of fluid in the cross flow conduit during plating.

Cross flow conduit for foaming prevention in high convection plating cells

Provided are cleaning methods and systems to remove unintended metallic deposits from electroplating apparatuses using reverse current deplating techniques. Such cleaning involves positioning a cleaning (deplating) disk in an electroplating cup similar to a regular processed substrate. The front surface of the cleaning disk includes a corrosion resistant conductive material to form electrical connections to deposits on the cup's surfaces. The disk is sealed in the cup and submerged into a plating solution. A reverse current is then applied to the front conductive surface of the disk to initiate deplating of the deposits. Sealing compression in the cup may change during cleaning to cause different deformation of the lip seal and to form new electrical connections to the deposits. The proposed cleaning may be applied to remove deposits formed during electroplating of alloys, in particular, tin-silver alloys widely used for semiconductor and wafer level packaging.

Cleaning electroplating substrate holders using reverse current deplating

Disclosed are electroplating cups for holding, sealing, and providing electrical power to wafers during electroplating, where the electroplating cup can include a cup bottom, an elastomeric lipseal, and an electrical contact element. The cup bottom can include a radially inwardly protruding surface with a plurality of through-holes. The elastomeric lipseal can directly adhere to the radially inwardly protruding surface of the cup bottom, fill the plurality of through-holes, and encircle an inner edge of the cup bottom. In some implementations, this can mitigate the effects of wafer sticking. In some implementations, the cup bottom may be treated to promote adhesion between the elastomeric lipseal and the radially inwardly protruding surface of the cup bottom.

Integrated elastomeric lipseal and cup bottom for reducing wafer sticking

An apparatus for continuous simultaneous electroplating of two metals having substantially different standard electrodeposition potentials (e.g., for deposition of Sn&#x2014;Ag alloys) comprises an anode chamber for containing an anolyte comprising ions of a first, less noble metal, (e.g., tin), but not of a second, more noble, metal (e.g., silver) and an active anode; a cathode chamber for containing catholyte including ions of a first metal (e.g., tin), ions of a second, more noble, metal (e.g., silver), and the substrate; a separation structure positioned between the anode chamber and the cathode chamber, where the separation structure substantially prevents transfer of more noble metal from catholyte to the anolyte; and fluidic features and an associated controller coupled to the apparatus and configured to perform continuous electroplating, while maintaining substantially constant concentrations of plating bath components for extended periods of use.

Protecting anodes from passivation in alloy plating systems

An apparatus for electroplating metal on a semiconductor substrate with improved plating uniformity includes in one aspect: a plating chamber configured to contain an electrolyte and an anode; a substrate holder configured to hold the semiconductor substrate; and an ionically resistive ionically permeable element comprising a substantially planar substrate-facing surface and an opposing surface, wherein the element allows for flow of ionic current towards the substrate during electroplating, and wherein the element comprises a region having varied local resistivity. In one example the resistivity of the element is varied by varying the thickness of the element. In some embodiments the thickness of the element is gradually reduced in a radial direction from the edge of the element to the center of the element. The provided apparatus and methods are particularly useful for electroplating metal in WLP recessed features.

Apparatus and method for electrodeposition of metals with the use of an ionically resistive ionically permeable element having spatially tailored resistivity

The embodiments herein relate to methods and apparatus for electroplating one or more materials onto a substrate. In many cases the material is a metal and the substrate is a semiconductor wafer, though the embodiments are no so limited. Typically, the embodiments herein utilize a channeled plate positioned near the substrate, creating a cross flow manifold defined on the bottom by the channeled plate, on the top by the substrate, and on the sides by a cross flow confinement ring. Also typically present is an edge flow element configured to direct electrolyte into a corner formed between the substrate and substrate holder. During plating, fluid enters the cross flow manifold both upward through the channels in the channeled plate, and laterally through a cross flow side inlet positioned on one side of the cross flow confinement ring. The flow paths combine in the cross flow manifold and exit at the cross flow exit, which is positioned opposite the cross flow inlet. These combined flow paths and the edge flow element result in improved plating uniformity, especially at the periphery of the substrate.

Dynamic modulation of cross flow manifold during electroplating

Disclosed are pre-wetting apparatus designs and methods for cleaning solid contaminants from substrates prior to through resist deposition of metal. In some embodiments, a pre-wetting apparatus includes a process chamber having a substrate holder, and at least one nozzle located directly above the wafer substrate and configured to deliver pre-wetting liquid (e.g., degassed deionized water) onto the substrate at a grazing angle of between about 5 and 45 degrees. In some embodiments the nozzle is a fan nozzle configured to deliver the liquid to the center of the substrate, such that the liquid first impacts the substrate in the vicinity of the center and then flows over the center of the substrate. In some embodiments the substrate is rotated unidirectionally or bidirectionally during pre-wetting with multiple accelerations and decelerations, which facilitate removal of contaminants.

Methods and apparatus for wetting pretreatment for through resist metal plating

Various embodiments herein relate to methods and apparatus for electroplating material onto substrates. Often the substrate is a semiconductor substrate. Various techniques described herein utilize a number of different electroplating stages, where the convection conditions vary between the different electroplating stages. In many cases, at least one ultra-low convection stage is used. The ultra-low convection stage may be paired with an initial stage and a final stage that have higher convection conditions. By controlling the convection conditions as described herein, very uniform plating results can be achieved, even when differently sized and/or shaped features are provided on a single substrate.

Convection optimization for mixed feature electroplating

Edge flow element for electroplating apparatus

Disclosed herein are methods of cleaning a lipseal and/or cup bottom of an electroplating device by removing metal deposits accumulated in prior electroplating operations. The methods may include orienting a nozzle such that it is pointed substantially at the inner circular edge of the lipseal and/or cup bottom, and dispensing a stream of cleaning solution from the nozzle such that the stream contacts the inner circular edge of the lipseal and/or cup bottom while they are being rotated, removing metal deposits. In some embodiments, the stream has a velocity component against the rotational direction of the lipseal and/or cup bottom. In some embodiments, the deposits may include a tin/silver alloy. Also disclosed herein are cleaning apparatuses for mounting in electroplating devices and for removing electroplated metal deposits from their lipseals and/or cup bottoms. In some embodiments, the cleaning apparatuses may include a jet nozzle.

Growing community of inventors

Beaverton, OR, United States of America

Lee Peng Chua