Asm America, Inc.

Asm International N.v.

Christophe F Pomarede

Eric James Shero

Michael A Todd

Keith Doran Weeks

Jeff Roberts

Christiaan J Werkhoven

Michael Eugene Givens

Cornelius A Van Der Jeugd

Jacobus Johannes Beulens

Marinus J De Blank

Yuet Mei Wan

Ruben Haverkort

Suvi P Haukka

Jan Willem Maes

Marko J Tuominen

Jan Willem Hub Maes

Olli Jylhä

Christian J Werkhoven

Fred AmRhein

Olli Jylh&auml;

Johan Swerts

Hilde De Witte

Multiple sequential processes are conducted in a reaction chamber to form ultra high quality silicon-containing compound layers, including silicon nitride layers. In a preferred embodiment, a silicon layer is deposited on a substrate using trisilane as the silicon precursor. A silicon nitride layer is then formed by nitriding the silicon layer. By repeating these steps, a silicon nitride layer of a desired thickness is formed.

Method to form ultra high quality silicon-containing compound layers

Methods are provided herein for forming electrode layers over high dielectric constant ('high k') materials. In the illustrated embodiments, a high k gate dielectric, such as zirconium oxide, is protected from reduction during a subsequent deposition of silicon-containing gate electrode. In particular, a seed deposition phase includes conditions designed for minimizing hydrogen reduction of the gate dielectric, including low hydrogen content, low temperatures and/or low partial pressures of the silicon source gas. Conditions are preferably changed for higher deposition rates and deposition continues in a bulk phase. Desirably, though, hydrogen diffusion is still minimized by controlling the above-noted parameters. In one embodiment, high k dielectric reduction is minimized through omission of a hydrogen carrier gas. In another embodiment, higher order silanes, aid in reducing hydrogen content for a given deposition rate.

Integration of high k gate dielectric

A nitrogen precursor that has been activated by exposure to a remotely excited species is used as a reactant to form nitrogen-containing layers. The remotely excited species can be, e.g., N, Ar, and/or He, which has been excited in a microwave radical generator. Downstream of the microwave radical generator and upstream of the substrate, the flow of excited species is mixed with a flow of NH. The excited species activates the NH. The substrate is exposed to both the activated NHand the excited species. The substrate can also be exposed to a precursor of another species to form a compound layer in a chemical vapor deposition. In addition, already-deposited layers can be nitrided by exposure to the activated NHand to the excited species, which results in higher levels of nitrogen incorporation than plasma nitridation using excited Nalone, or thermal nitridation using NHalone, with the same process temperatures and nitridation durations.

Remote plasma activated nitridation

A high k dielectric film and methods for forming the same are disclosed. The high k material includes two peaks of impurity concentration, particularly nitrogen, such as at a lower interface and upper interface, making the layer particularly suitable for transistor gate dielectric applications. The methods of formation include low temperature processes, particularly CVD using a remote plasma generator and atomic layer deposition using selective incorporation of nitrogen in the cyclic process. Advantageously, nitrogen levels are tailored during the deposition process and temperatures are low enough to avoid interdiffusion and allow maintenance of the desired impurity profile.

Incorporation of nitrogen into high k dielectric film

Methods are provided herein for treating substrate surfaces in preparation for subsequent nucleation-sensitive depositions (e.g., polysilicon or poly-SiGe) and adsorption-driven deposition (e.g. atomic layer deposition or ALD). Prior to depositing, the surface is treated with non-depositing plasma products. The treated surface more readily nucleates polysilicon and poly-SiGe (such as for a gate electrode), or more readily adsorbs ALD reactants (such as for a gate dielectric). The surface treatment provides surface moieties more readily susceptible to a subsequent deposition reaction, or more readily susceptible to further surface treatment prior to deposition. By changing the surface termination of the substrate with a low temperature radical treatment, subsequent deposition is advantageously facilitated without depositing a layer of any appreciable thickness and without significantly affecting the bulk properties of the underlying material. Preferably less than 10 &#x212b; of the bulk material incorporates the excited species, which can include fluorine, chlorine and particularly nitrogen excited species.

Surface preparation prior to deposition

Sequential processes are conducted in a batch reaction chamber to form ultra high quality silicon-containing compound layers, e.g., silicon nitride layers, at low temperatures. Under reaction rate limited conditions, a silicon layer is deposited on a substrate using trisilane as the silicon precursor. Trisilane flow is interrupted. A silicon nitride layer is then formed by nitriding the silicon layer with nitrogen radicals, such as by pulsing the plasma power (remote or in situ) on after a trisilane step. The nitrogen radical supply is stopped. Optionally non-activated ammonia is also supplied, continuously or intermittently. If desired, the process is repeated for greater thickness, purging the reactor after each trisilane and silicon compounding step to avoid gas phase reactions, with each cycle producing about 5-7 angstroms of silicon nitride.

Low temperature silicon compound deposition

Methods are provided herein for forming electrode layers over high dielectric constant ('high k') materials. In the illustrated embodiments, a high k gate dielectric, such as zirconium oxide, is protected from reduction during a subsequent deposition of silicon-containing gate electrode. In particular, a seed deposition phase includes conditions designed for minimizing hydrogen reduction of the gate dielectric, including low hydrogen content, low temperatures and/or low partial pressures of the silicon source gas. Conditions are preferably changed for higher deposition rates and deposition continues in a bulk phase. Desirably, though, hydrogen diffusion is still minimized by controlling the above-noted parameters. In one embodiment, high k dielectric reduction is minimized through omission of a hydrogen carrier gas. In another embodiment, higher order silanes aid in reducing hydrogen content for a given deposition rate.

In accordance with one aspect of the present invention, a method is provided for transporting a workpiece in a semiconductor processing apparatus comprising a transfer chamber, a process chamber, and a gate valve between the transfer chamber and the process chamber. The method comprises vacuum pumping the transfer chamber to achieve a first pressure in the transfer chamber and vacuum pumping the process chamber to achieve a second pressure in the process chamber. An inert gas is flowed into the transfer chamber and shut off in the process chamber. The transfer chamber is isolated from pumping, but pumping continues from the process chamber. The gate valve is opened after isolating the transfer chamber from pumping. The workpiece is then transferred between the transfer chamber and the process chamber. A definitive flow direction from transfer chamber to process chamber is thereby achieved, minimizing risk of back-diffusion.

Reduced cross-contamination between chambers in a semiconductor processing tool

A protective coating is provided herein and methods of using the protective coating for susceptors used in semiconductor deposition chambers are described. In the preferred embodiments, CVD chamber equipment, such as a susceptor, is protected from plasma etch cleaning. Prior to CVD of silicon nitride, the chamber equipment is first coated with an emissivity-stabilizing layer, such as silicon nitride. This layer is then superficially oxidized. After repeated cycles of deposited silicon nitride upon different substrates in sequence, the chamber is emptied of wafers and a plasma cleaning process is conducted. Plasma cleaning is preferably selective against the silicon oxynitride protective coating. After the plasma cleaning process, the emissivity-stabilizing layer is reapplied, oxidized, and a plurality of deposition cycles can commence again.

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Phoenix, AZ, United States of America

Christophe F Pomarede