Novellus Systems Patent Grants

Electrolyte concentration control system for high rate electroplating

Granted: August 18, 2015
Patent Number: 9109295
An electroplating apparatus for filling recessed features on a semiconductor substrate includes an electrolyte concentrator configured for concentrating an electrolyte having Cu2+ ions to form a concentrated electrolyte solution that would have been supersaturated at 20° C. The electrolyte is maintained at a temperature that is higher than 20° C., such as at least at about 40° C. The apparatus further includes a concentrated electrolyte reservoir and a plating cell, where the plating…

Method of depositing a diffusion barrier for copper interconnect applications

Granted: August 4, 2015
Patent Number: 9099535
The present invention pertains to methods for forming a metal diffusion barrier on an integrated circuit wherein the formation includes at least two operations. The first operation deposits barrier material via PVD or CVD to provide some minimal coverage. The second operation deposits an additional barrier material and simultaneously etches a portion of the barrier material deposited in the first operation. The result of the operations is a metal diffusion barrier formed in part by net…

High temperature electrode connections

Granted: July 21, 2015
Patent Number: 9088085
Embodiments include a high temperature electrode connection assembly for a wafer-processing pedestal. The high temperature electrode connection assembly includes an electrode rod having a cup that mounts to a stud embedded in the pedestal and a plate adapter portion. The assembly also includes a floating plate having an outer surface and an aperture for receiving the electrode rod. The floating plate contacts an inner surface of the pedestal to resist lateral movement of the electrode…

Hybrid impedance matching for inductively coupled plasma system

Granted: July 14, 2015
Patent Number: 9082589
In one aspect, a system includes a generator configured to generate and tune a frequency of a supply signal. The system includes an auto-matching network configured to receive the supply signal and to generate an impedance-matched signal for use in powering a plasma system. In some implementations, during a first stage of an impedance matching operation, the generator is configured to tune the frequency of the supply signal until the generator identifies a frequency for which the…

Method for producing ultra-thin tungsten layers with improved step coverage

Granted: July 7, 2015
Patent Number: 9076843
A tungsten nucleation film is formed on a surface of a semiconductor substrate by alternatively providing to that surface, reducing gases and tungsten-containing gases. Each cycle of the method provides for one or more monolayers of the tungsten film. The film is conformal and has improved step coverage, even for a high aspect ratio contact hole.

Reduced isotropic etchant material consumption and waste generation

Granted: July 7, 2015
Patent Number: 9074287
Methods and apparatus for isotropically etching a metal from a work piece, while recovering and reconstituting the chemical etchant are described. Various embodiments include apparatus and methods for etching where the recovered and reconstituted etchant is reused in a continuous loop recirculation scheme. Steady state conditions can be achieved where these processes are repeated over and over with occasional bleed and feed to replenish reagents and/or adjust parameters such as pH, ionic…

Wet etching methods for copper removal and planarization in semiconductor processing

Granted: July 7, 2015
Patent Number: 9074286
Exposed copper regions on a semiconductor substrate can be etched by a wet etching solution comprising (i) one or more complexing agents selected from the group consisting of bidentate, tridentate, and quadridentate complexing agents; and (ii) an oxidizer, at a pH of between about 5 and 12. In many embodiments, the etching is substantially isotropic and occurs without visible formation of insoluble species on the surface of copper. The etching is useful in a number of processes in…

Method and apparatuses for reducing porogen accumulation from a UV-cure chamber

Granted: July 7, 2015
Patent Number: 9073100
Porogen accumulation in a UV-cure chamber is reduced by removing outgassed porogen through a heated outlet while purge gas is flowed across a window through which a wafer is exposed to UV light. A purge ring having specific major and minor exhaust to inlet area ratios may be partially made of flame polished quartz to improve flow dynamics. The reduction in porogen accumulation allows more wafers to be processed between chamber cleans, thus improving throughput and cost.

Method for depositing a chlorine-free conformal sin film

Granted: June 30, 2015
Patent Number: 9070555
Described are methods of making silicon nitride (SiN) materials on substrates. Improved SiN films made by the methods are also included. One aspect relates to depositing chlorine (Cl)-free conformal SiN films. In some embodiments, the SiN films are Cl-free and carbon (C)-free. Another aspect relates to methods of tuning the stress and/or wet etch rate of conformal SiN films. Another aspect relates to low-temperature methods of depositing high quality conformal SiN films. In some…

Methods for reducing metal oxide surfaces to modified metal surfaces using a gaseous reducing environment

Granted: June 30, 2015
Patent Number: 9070750
Method and apparatus for reducing metal oxide surfaces to modified metal surfaces are disclosed. Metal oxide surfaces are reduced to form a film integrated with a metal seed layer on a substrate by exposing the metal oxide surfaces to a reducing gas atmosphere comprising radicals of a reducing gas species. The radicals of the reducing gas species can form from exposing the reducing gas species to ultraviolet radiation and/or a plasma. The substrate is maintained at a temperature below a…

Flowable oxide deposition using rapid delivery of process gases

Granted: June 23, 2015
Patent Number: 9064684
Methods and apparatus for filling gaps on partially manufactured semiconductor substrates with dielectric material are provided. In certain embodiments, the methods include introducing a first process gas into the processing chamber and accumulating a second process gas in an accumulator maintained at a pressure level substantially highest than that of the processing chamber pressure level. The second process gas is then rapidly introduced from the accumulator into the processing…

Progressive UV cure

Granted: June 9, 2015
Patent Number: 9050623
Porous ULK film is cured with UV radiation at progressively shorter wavelengths to obtain ULK films quickly at a desired dielectric constant with improved mechanical properties. At longer wavelengths above about 220 nm or about 240 nm, porogen is removed while minimizing silicon-carbon bond formation. At shorter wavelengths, mechanical properties are improved while dielectric constant increases.

Control of electrolyte composition in a copper electroplating apparatus

Granted: June 2, 2015
Patent Number: 9045841
In a copper electroplating apparatus having separate anolyte and catholyte portions, the concentration of anolyte components (e.g., acid or copper salt) is controlled by providing a diluent to the recirculating anolyte. The dosing of the diluent can be controlled by the user and can follow a pre-determined schedule. For example, the schedule may specify the diluent dosing parameters, so as to prevent precipitation of copper salt in the anolyte. Thus, precipitation-induced anode…

Dynamic current distribution control apparatus and method for wafer electroplating

Granted: June 2, 2015
Patent Number: 9045840
Methods, systems, and apparatus for plating a metal onto a work piece are described. In one aspect, an apparatus includes a plating chamber, a substrate holder, an anode chamber housing an anode, and an ionically resistive ionically permeable element positioned between a substrate and the anode chamber during electroplating. The anode chamber may be movable with respect to the ionically resistive ionically permeable element to vary a distance between the anode chamber and the ionically…

Removal of native oxide with high selectivity

Granted: May 19, 2015
Patent Number: 9034773
Provided are methods and systems for removing a native silicon oxide layer on a wafer. In a non-sequential approach, a wafer is provided with a native silicon oxide layer on a polysilicon layer. An etchant including a hydrogen-based species and a fluorine-based species is introduced, exposed to a plasma, and flowed onto the wafer at a relatively low temperature. The wafer is then heated to a slightly elevated temperature to substantially remove the native oxide layer. In a sequential…

Depositing tungsten into high aspect ratio features

Granted: May 19, 2015
Patent Number: 9034768
Methods and apparatuses for filling high aspect ratio features with tungsten-containing materials are provided. The method involves providing a partially fabricated semiconductor substrate and depositing a tungsten-containing layer on the substrate surface to partially fill one or more high aspect ratio features. The method continues with selective removal of a portion of the deposited layer such that more material is removed near the feature opening than inside the feature. In certain…

Methods of forming tensile tungsten films and compressive tungsten films

Granted: May 19, 2015
Patent Number: 9034760
Methods, apparatus, and systems for depositing tensile or compressive tungsten films are described. In one aspect, a method includes providing a substrate to a chamber. The substrate has a field region and a feature recessed from the field region. Then, the substrate is exposed to an organometallic tungsten precursor. The organometallic tungsten precursor not adsorbed onto the substrate is removed from the chamber. The substrate is treated with a first treatment including a heat…

Temperature controlled showerhead for high temperature operations

Granted: May 19, 2015
Patent Number: 9034142
A temperature controlled showerhead assembly for chemical vapor deposition (CVD) chambers enhances heat dissipation to provide accurate temperature control of the showerhead face plate and maintain temperatures substantially lower than surrounding components. Heat dissipates by conduction through a showerhead stem and removed by the heat exchanger mounted outside of the vacuum environment. Heat is supplied by a heating element inserted into the steam of the showerhead. Temperature is…

Front referenced anode

Granted: May 12, 2015
Patent Number: 9028657
Apparatus and methods for electroplating are described. Apparatus described herein include anode supports including positioning mechanisms that maintain a consistent distance between the surface of the wafer and the surface of a consumable anode during plating. Greater uniformity control is achieved.

Wetting wave front control for reduced air entrapment during wafer entry into electroplating bath

Granted: May 12, 2015
Patent Number: 9028666
Methods described herein manage wafer entry into an electrolyte so that air entrapment due to initial impact of the wafer and/or wafer holder with the electrolyte is reduced and the wafer is moved in such a way that an electrolyte wetting wave front is maintained throughout immersion of the wafer also minimizing air entrapment.