Novellus Systems Incorporated

Joe Womack

Mandyam Sriram

Keith Fox

Bart Jan Van Schravendijk

George Andrew Antonelli

Jennifer O'Loughlin

Dong Niu

Pramod Subramonium

Patrick G Breiling

John B Alexy

Jason Dirk Haverkamp

Sirish K Reddy

Alice Hollister

Smooth silicon films having low compressive stress and smooth tensile silicon films are deposited by plasma enhanced chemical vapor deposition (PECVD) using a process gas comprising a silicon-containing precursor (e.g., silane), argon, and a second gas, such as helium, hydrogen, or a combination of helium and hydrogen. Doped smooth silicon films and smooth silicon germanium films can be obtained by adding a source of dopant or a germanium-containing precursor to the process gas. In some embodiments dual frequency plasma comprising high frequency (HF) and low frequency (LF) components is used during deposition, resulting in improved film roughness. The films are characterized by roughness (Ra) of less than about 7 &#x212b;, such as less than about 5 &#x212b; as measured by atomic force microscopy (AFM), and a compressive stress of less than about 500 MPa in absolute value. In some embodiments smooth tensile silicon films are obtained.

PECVD deposition of smooth silicon films

Methods of forming a film stack may include the plasma accelerated deposition of a silicon nitride film formed from the reaction of nitrogen containing precursor with silicon containing precursor, the plasma accelerated substantial elimination of silicon containing precursor from the processing chamber, the plasma accelerated deposition of a silicon oxide film atop the silicon nitride film formed from the reaction of silicon containing precursor with oxidant, and the plasma accelerated substantial elimination of oxidant from the processing chamber. Process station apparatuses for forming a film stack of silicon nitride and silicon oxide films may include a processing chamber, one or more gas delivery lines, one or more RF generators, and a system controller having machine-readable media with instructions for operating the one or more gas delivery lines, and the one or more RF generators.

In-situ deposition of film stacks

Methods for depositing film stacks by plasma enhanced chemical vapor deposition are described. In one example, a method for depositing a film stack on a substrate, wherein the film stack includes films of different compositions and the deposition is performed in a process station in-situ, is provided. The method includes, in a first plasma-activated film deposition phase, depositing a first layer of film having a first film composition on the substrate; in a second plasma-activated deposition phase, depositing a second layer of film having a second film composition on the first layer of film; and sustaining the plasma while transitioning a composition of the plasma from the first plasma-activated film deposition phase to the second plasma-activated film deposition phase.

Methods and hardware for depositing ultra-smooth silicon-containing films and film stacks are described. In one example, an embodiment of a method for forming a silicon-containing film on a substrate in a plasma-enhanced chemical vapor deposition apparatus is disclosed, the method including supplying a silicon-containing reactant to the plasma-enhanced chemical vapor deposition apparatus; supplying a co-reactant to the plasma-enhanced chemical vapor deposition apparatus; supplying a capacitively-coupled plasma to a process station of the plasma-enhanced chemical vapor deposition apparatus, the plasma including silicon radicals generated from the silicon-containing reactant and co-reactant radicals generated from the co-reactant; and depositing the silicon-containing film on the substrate, the silicon-containing film having a refractive index of between 1.4 and 2.1, the silicon-containing film further having an absolute roughness of less than or equal to 4.5 &#x212b; as measured on a silicon substrate.

Smooth silicon-containing films

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Tigard, OR, United States of America

Joe Womack