Kovio, Inc.

Thin Film Electronics Asa

Fabio Zürcher

Joerg Rockenberger

James Montague Cleeves

Wenzhuo Guo

Brent Ridley

Klaus Kunze

Vladimir K Dioumaev

Arvind Kamath

Erik C Scher

Patrick Smith

Mao Takashima

Scott T Haubrich

Dmitry Karshtedt

Yu Chen

Aditi Chandra

Laila Francisco

Epitaxial structures, methods of making epitaxial structures, and devices incorporating such epitaxial structures are disclosed. The methods and the structures employ a liquid-phase Group IVA semiconductor element precursor ink (e.g., including a cyclo- and/or polysilane) and have a relatively good film quality (e.g., texture, density and/or purity). The Group IVA semiconductor element precursor ink forms an epitaxial film or feature when deposited on a (poly)crystalline substrate surface and heated sufficiently for the Group IVA semiconductor precursor film or feature to adopt the (poly)crystalline structure of the substrate surface. Devices incorporating a selective emitter that includes the present epitaxial structure may exhibit improved power conversion efficiency relative to a device having a selective emitter made without such a structure due to the improved film quality and/or the perfect interface formed in regions between the epitaxial film and contacts formed on the film.

Epitaxial structures and methods of forming the same

Metal ink compositions, methods of forming such compositions, and methods of forming conductive layers are disclosed. The ink composition includes a bulk metal, a transition metal source, and an organic solvent. The transition metal source may be a transition metal capable of forming a silicide, in an amount providing from 0.01 to 50 at. % of the transition metal relative to the bulk metal. Conductive structures may be made using such ink compositions by forming a silicon-containing layer on a substrate, printing a metal ink composition on the silicon-containing layer, and curing the composition. The metal inks of the present invention have high conductivity and form low resistivity contacts with silicon, and reduce the number of inks and printing steps needed to fabricate integrated circuits.

Metal inks for improved contact resistance

Heterocyclosilane compounds and methods for making the same. Such compounds (and/or ink compositions containing the same) are useful for printing or spin coating a doped silane film onto a substrate that can easily be converted into a doped amorphous silicon film (that may also be hydrogenated to some extent) or doped polycrystalline semiconductor film suitable for electronic devices. Thus, the present invention advantageously provides commercial qualities and quantities of doped semiconductor films from a 'doped liquid silicon' composition.

Heterocyclic semiconductor precursor compounds, compositions containing the same, and methods of making such compounds and compositions

Dopant-group substituted (cyclo)silane compounds, liquid-phase compositions containing such compounds, and methods for making the same. Such compounds (and/or ink compositions containing the same) are useful for printing or spin coating a doped silane film onto a substrate that can easily be converted into a doped amorphous or polycrystalline silicon film suitable for electronic devices. Thus, the present invention advantageously provides commercial qualities and quantities of doped semiconductor films from a doped 'liquid silicon' composition.

Dopant group-substituted semiconductor precursor compounds, compositions containing the same, and methods of making such compounds and compositions

A method of making hydrogenated Group IVA compounds having reduced metal-based impurities, compositions and inks including such Group IVA compounds, and methods for forming a semiconductor thin film. Thin semiconducting films prepared according to the present invention generally exhibit improved conductivity, film morphology and/or carrier mobility relative to an otherwise identical structure made by an identical process, but without the washing step. In addition, the properties of the present thin film are generally more predictable than those of films produced from similarly prepared (cyclo)silanes that have not been washed according to the present invention. The present invention advantageously provides semiconducting thin film structures having qualities suitable for use in electronics applications, such as display devices or RF ID tags, while enabling high-throughput manufacturing processes that form such thin films in seconds or minutes, rather than hours or days as with conventional photolithographic processes.

Method of making a silicon-containing film

Doped semiconductor ink formulations, methods of making doped semiconductor ink formulations, methods of coating or printing thin films, methods of forming electronic devices and/or structures from the thin films, and methods for modifying and controlling the threshold voltage of a thin film transistor using the films are disclosed. A desired dopant may be added to an ink formulation comprising a Group IVA compound and a solvent, and then the ink may be printed on a substrate to form thin films and conductive structures/devices, such as thin film transistors. By adding a customized amount of the dopant to the ink prior to printing, the threshold voltage of a thin film transistor made from the doped semiconductor ink may be independently controlled upon activation of the dopant.

Method for modifying and controlling the threshold voltage of thin film transistors

Compositions and methods for controlled polymerization and/or oligomerization of hydrosilanes compounds including those of the general formulae SiHand SiHas well as alkyl- and arylsilanes, to produce soluble silicon polymers as a precursor to silicon films having low carbon content.

Silicon polymers, methods of polymerizing silicon compounds, and methods of forming thin films from such silicon polymers

Methods for forming doped silane and/or semiconductor thin films, doped liquid phase silane compositions useful in such methods, and doped semiconductor thin films and structures. The composition is generally liquid at ambient temperatures and includes a Group IVA atom source and a dopant source. By irradiating a doped liquid silane during at least part of its deposition, a thin, substantially uniform doped oligomerized/polymerized silane film may be formed on a substrate. Such irradiation is believed to convert the doped silane film into a relatively high-molecular weight species with relatively high viscosity and relatively low volatility, typically by cross-linking, isomerization, oligomerization and/or polymerization. A film formed by the irradiation of doped liquid silanes can later be converted (generally by heating and annealing/recrystallization) into a doped, hydrogenated, amorphous silicon film or a doped, at least partially polycrystalline silicon film suitable for electronic devices. Thus, the present invention enables use of high throughput, low cost equipment and techniques for making doped semiconductor films of commercial quality and quantity from doped 'liquid silicon.'

Methods of forming a doped semiconductor thin film, doped semiconductor thin film structures, doped silane compositions, and methods of making such compositions

A method for making an electronic device, such as a MOS transistor, including the steps of forming a plurality of semiconductor islands on an electrically functional substrate, printing a first dielectric layer on or over a first subset of the semiconductor islands and optionally a second dielectric layer on or over a second subset of the semiconductor islands, and annealing. The first dielectric layer contains a first dopant, and the (optional) second dielectric layer contains a second dopant different from the first dopant. The dielectric layer(s), semiconductor islands and substrate are annealed sufficiently to diffuse the first dopant into the first subset of semiconductor islands and, when present, the second dopant into the second subset of semiconductor islands.

Printed dopant layers

Printable metal formulations, methods of making the formulations, and methods of coating or printing thin films from metal ink precursors are disclosed. The metal formulation generally includes one or more Group 4, 5, 6, 7, 8, 9, 10, 11, or 12 metal salts or metal complexes, one or more solvents adapted to facilitate coating and/or printing of the formulation, and one or more optional additives that form (only) gaseous or volatile byproducts upon reduction of the metal salt or metal complex to an elemental metal and/or alloy thereof. The formulation may be made by combining the metal salt(s) or metal complex(es) and the solvent(s), and dissolving the metal salt(s) or metal complex(es) in the solvent(s) to form the formulation. Thin films may be made by coating or printing the metal formulation on a substrate; removing the solvents to form a metal-containing precursor film; and reducing the metal-containing precursor film.

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Brisbane, CA, United States of America

Fabio Zürcher