International Business Machines Corporation

Other

Thomas John Licata

James Gardner Ryan

Alfred Grill

Cyril Cabral, Jr

Christopher Vincent Jahnes

Donald M Kenney

Paul David Agnello

Ronnen Andrew Roy

Jack Allan Mandelman

Michael D Armacost

Wayne S Berry

A Richard Baker, Jr

Daniel Arthur Carl

Rajiv V Joshi

Timothy Dooling Sullivan

Kenneth Parker Rodbell

Herbert Lei Ho

Katsuya Okumura

Peter John Geiss

Ronald Wayne Nunes

Kurt R Kimmel

Richard Steven Kontra

Motoya Okazaki

Julian Juu-Chuan Hsieh

A method of enhancing the aluminum interconnect properties in very fine metalization patterns interconnecting integrated circuits that improves the texture and electromigration resistance of aluminum in thin films. Enhanced performance can be obtained by forming a smooth oxide layer in situ, or by surface conditioning a previously formed oxide layer in an appropriate manner to provide the requisite surface smoothness, then by refining the aluminum microstructure by hot deposition or ex-situ heat treatment.

Method for enhancing aluminum interconnect properties

Capacitive coupling, and attendant cross-talk, is reduced by increasing the distance between wire surfaces in integrated circuit applications. This is done by changing wire shape from the conventional rectangular cross-section. A cross-section which consists of a rectangular portion and a shaped, triangular portion is created, having the effect of increasing the effective distance between adjacent conductors. Cross-sectional area of wires is maintained and thus the current carrying capacity is maintained. The wire shapes may be produced using several alternate methods.

Wire shape conferring reduced crosstalk and formation methods

An apparatus and method provide deposition on a surface by angled sputtering using a collimation grid having angled vanes which limit the distribution of trajectories of particles in at least one coordinate direction around a central axis oriented at an angle of less than 90.degree. to said surface; resulting in improved uniformity of deposition and/or selective favoring of deposition on surfaces at a high angle to the deposition surface (e.g. sidewalls). Substantially parallel orientation and uniform spacing of the sputtering target and deposition surface provides good uniformity of results over the deposition surface. The angled trajectories of sputtered particles provides improved deposition on sides of upstanding mandrel features and filling of recessed features of high aspect ratio, especially when the collimation grid is rotated about an axis generally perpendicular to the deposition surface. Angled, collimated deposition also allows for control of deposition at potentially sub-lithographic feature sizes by using portions of features as a mask with deposition being performed only on remaining exposed portions of features or deposition on selected sides of a mandrel feature. Sidewall image transfer techniques may thus be extended to non-symmetrical and singular features. At very shallow angles to the deposition surface, deposited material has a fibrous texture with greatly increased effective surface area.

Method for selective material deposition on one side of raised or

A process for forming a dual-damascene interconnect employs a spun-on organic layer above an interlayer dielectric having a set of apertures for vias that forms tapered regions about the apertures without penetrating the apertures; the slope of the tapered regions being transferred in the etching process to form self-aligned tapered vias.

Dual damascene process having tapered vias

A multilayer structure having an oxygen or dopant diffusion barrier fabricated of an electrically conductive, thermally stable material of refractory metal-silicon-nitrogen which is resistant to oxidation, prevents out-diffusion of dopants from silicon and has a wide process window wherein the refractory metal is selected from Ta, W, Nb, V, Ti, Zr, Hf, Cr and Mo.

Tasin oxygen diffusion barrier in multilayer structures

A method of forming recesses in a substrate such as a capacitor so as to increase the surface area thereof and therefore the charge storage capacity of the capacitor. This is accomplished by utilizing a micro mask formed by agglomeration on the surface of the substrate. The agglomerated material, such as gold, titanium nitride or titanium silicide, is used as a mask for selectively etching the substrate to form recesses therein. Alternatively, an oxide transfer mask can be utilized with the agglomerated material micro mask to etch the substrate.

Micro mask comprising agglomerated material

An damascene x-ray mask comprises an oxide membrane layer having trenches formed therein defining an x-ray mask pattern. The trenches are filled with collimated, sputtered tungsten sputtered in a relatively high pressure environment. The result is a dense, low stress tungsten film completely filling the trenches. Damascene refers to the process by which the mask is formed. The mask is formed on a silicon substrate and then the substrate is etched away from the bottom side leaving substantially just the oxide layer and the collimated tungsten. The oxide layer is transparent to x-rays and the collimated tungsten layer is opaque to x-rays.

Tungsten absorber for x-ray mask

An improved process for depositing a conductive thin film upon an integrated circuit substrate by collimated sputtering is disclosed. The sputtered films are alloys of aluminum; a preferred alloying metal is magnesium. The sputtered films of the invention have a more uniform orientation of grains than sputtered aluminum copper silicon alloy films. Such processes are especially useful in the fabrication of integrated circuit devices having aluminum alloy wiring elements.

Process for depositing a conductive thin film upon an integrated circuit

An improved method of forming interlayer interconnections employs the same material (or materials that are etched similarly) for both the stud and the upper interconnect in which the stud is surrounded by a collar of conductive material that is also resistant to the etching process used to define the upper wire interconnect.

Conductive rie-resistant collars for studs beneath rie-defined wires

The subject invention provides a method of forming recesses in a substrate such as a capacitor so as to increase the surface area thereof and therefore the charge storage capacity of the capacitor. This is accomplished by utilizing a micro mask formed by agglomeration on the surface of the substrate. The agglomerated material, such as gold, titanium nitride or titanium silicide, is used as a mask for selectively etching the substrate to form recesses therein. Alternatively, an oxide transfer mask can be utilized with the agglomerated material micro mask to etch the substrate.

An epitaxial cobalt silicide film is formed using a thin metal underlayer, which is placed underneath a cobalt layer prior to a heating step which forms the silicide film. More specifically, a refractory metal layer comprising tungsten, chromium, molybdenum, or a silicide thereof, is formed overlying a silicon substrate on a semiconductor wafer. A cobalt layer is formed overlying the refractory metal layer. Next, the wafer is annealed at a temperature sufficiently high to form an epitaxial cobalt silicide film overlying the silicon substrate. Following this annealing step, a cobalt-silicon-refractory metal alloy remains overlying the epitaxial cobalt silicide film. This silicide is then used to form a shallow P-N junction by dopant out-diffusion. First, either a P or N-type dopant is implanted into the silicide film so that substantially none of the dopant is implanted into the underlying silicon substrate. After implanting, the dopant is out-diffused from the silicide film into the underlying silicon substrate at a drive temperature sufficiently high to form the desired P-N junction.

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Lagrangeville, NY, United States of America

Thomas John Licata