Abstract: A method of etching carbon films on patterned heterogeneous structures is described and includes a gas phase etch using remote plasma excitation. The remote plasma excites a fluorine-containing precursor and an oxygen-containing precursor, the plasma effluents created are flowed into a substrate processing region. The plasma effluents etch the carbon film more rapidly than silicon, silicon nitride, silicon carbide, silicon carbon nitride and silicon oxide.

Abstract: A method of anisotropically dry-etching exposed substrate material on a patterned substrate is described. The patterned substrate has a gap formed in a single material made from, for example, a silicon-containing material or a metal-containing material. The method includes directionally ion-implanting the patterned structure to implant the bottom of the gap without implanting substantially the walls of the gap. Subsequently, a remote plasma is formed using a fluorine-containing precursor to etch the patterned substrate such that either (1) the walls are selectively etched relative to the floor of the gap, or (2) the floor is selectively etched relative to the walls of the gap. Without ion implantation, the etch operation would be isotropic owing to the remote nature of the plasma excitation during the etch process.

Abstract: A method of removing titanium nitride hardmask is described. The hardmask resides above a low-k dielectric layer prior to removal and the low-k dielectric layer retains a relatively low net dielectric constant after the removal process. The low-k dielectric layer may be part of a dual damascene structure having copper at the bottom of the vias. A non-porous carbon layer is deposited prior to the titanium nitride hardmask removal to protect the low-k dielectric layer and the copper. The titanium nitride hardmask and the non-porous carbon layer are removed with a gas-phase etch using plasma effluents formed in a remote plasma from a chlorine-containing precursor. Plasma effluents within the remote plasma are flowed into a substrate processing region where the plasma effluents react with the non-porous carbon layer and the titanium nitride.

Abstract: A tunable plasma etch process includes generating a plasma in a controlled flow of a source gas including NH3 and NF3 to form a stream of plasma products, controlling a flow of un-activated NH3 that is added to the stream of plasma products to form an etch gas stream; and controlling pressure of the etch gas stream by adjusting at least one of the controlled flow of the source gas and the flow of un-activated NH3 until the pressure is within a tolerance of a desired pressure. An etch rate of at least one of polysilicon and silicon dioxide by the etch gas stream is adjustable by varying a ratio of the controlled flow of the source gas to the flow of un-activated NH3.

Abstract: Methods of producing V-shaped trenches in crystalline substrates are described. The methods involve processing a patterned substrate with etch masking materials defining each side of exposed silicon (100). The exposed silicon (100) is exposed to remotely-excited halogen-containing precursor including chlorine or bromine. The plasma effluents formed from the halogen-containing precursor preferentially remove silicon from all exposed facets other than silicon (111). Etching the crystalline substrates with the plasma effluents produce at least two silicon (111) facets between two adjacent masking elements. Forming the silicon (111) facets may be accelerated by pretreating the crystalline substrates using a halogen-containing precursor locally excited in a biased plasma to initiate the generation of the trench.

Abstract: A method of removing titanium nitride hardmask is described. The hardmask resides above a low-k dielectric layer prior to removal and the low-k dielectric layer retains a relatively low net dielectric constant after the removal process. The low-k dielectric layer may be part of a dual damascene structure having copper at the bottom of the vias. A non-porous carbon layer is deposited prior to the titanium nitride hardmask removal to protect the low-k dielectric layer and the copper. The titanium nitride hardmask is removed with a gas-phase etch using plasma effluents formed in a remote plasma from a fluorine-containing precursor. Plasma effluents within the remote plasma are flowed into a substrate processing region where the plasma effluents react with the titanium nitride.

Abstract: A method of etching exposed titanium oxide on heterogeneous structures is described and includes a remote plasma etch formed from a fluorine-containing precursor. Plasma effluents from the remote plasma are flowed into a substrate processing region where the plasma effluents may combine with a nitrogen-containing precursor such as an amine (N:) containing precursor. Reactants thereby produced etch the patterned heterogeneous structures with high titanium oxide selectivity while the substrate is at elevated temperature. Titanium oxide etch may alternatively involve supplying a fluorine-containing precursor and a source of nitrogen-and-hydrogen-containing precursor to the remote plasma. The methods may be used to remove titanium oxide while removing little or no low-K dielectric, polysilicon, silicon nitride or titanium nitride.

Abstract: Embodiments of the present technology may include a method of etching a substrate. The method may include striking a plasma discharge in a plasma region. The method may also include flowing a fluorine-containing precursor into the plasma region to form a plasma effluent. The plasma effluent may flow into a mixing region. The method may further include introducing a hydrogen-and-oxygen-containing compound into the mixing region without first passing the hydrogen-and-oxygen-containing compound into the plasma region. Additionally, the method may include reacting the hydrogen-and-oxygen-containing compound with the plasma effluent in the mixing region to form reaction products. The reaction products may flow through a plurality of openings in a partition to a substrate processing region. The method may also include etching the substrate with the reaction products in the substrate processing region.

Abstract: Methods of forming self-aligned structures on patterned substrates are described. The methods may be used to form metal lines or vias without the use of a separate photolithography pattern definition operation. Self-aligned contacts may be produced regardless of the presence of spacer elements. The methods include directionally ion-implanting a gapfill portion of a gapfill silicon oxide layer to implant into the gapfill portion without substantially ion-implanting the remainder of the gapfill silicon oxide layer (the sidewalls). Subsequently, a remote plasma is formed using a fluorine-containing precursor to etch the patterned substrate such that the gapfill portions of silicon oxide are selectively etched relative to other exposed portions exposed parallel to the ion implantation direction. Without ion implantation, the etch operation would be isotropic owing to the remote nature of the plasma excitation during the etch process.

Abstract: A method of selectively etching silicon nitride from a substrate comprising a silicon nitride layer and a silicon oxide layer includes flowing a fluorine-containing gas into a plasma generation region of a substrate processing chamber and applying energy to the fluorine-containing gas to generate a plasma in the plasma generation region. The plasma comprises fluorine radicals and fluorine ions. The method also includes filtering the plasma to provide a reactive gas having a higher concentration of fluorine radicals than fluorine ions and flowing the reactive gas into a gas reaction region of the substrate processing chamber. The method also includes exposing the substrate to the reactive gas in the gas reaction region of the substrate processing chamber. The reactive gas etches the silicon nitride layer at a higher etch rate than the reactive gas etches the silicon oxide layer.

Abstract: A method of etching patterned heterogeneous silicon-containing structures is described and includes a remote plasma etch with inverted selectivity compared to existing remote plasma etches. The methods may be used to conformally trim polysilicon while removing little or no silicon oxide. More generally, silicon-containing films containing less oxygen are removed more rapidly than silicon-containing films which contain more oxygen. Other exemplary applications include trimming silicon carbon nitride films while essentially retaining silicon oxycarbide. Applications such as these are enabled by the methods presented herein and enable new process flows. These process flows are expected to become desirable for a variety of finer linewidth structures. Methods contained herein may also be used to etch silicon-containing films faster than nitrogen-and-silicon containing films having a greater concentration of nitrogen.

Abstract: Methods are described herein for etching metal films which are difficult to volatize. The methods include exposing a metal film to a chlorine-containing precursor (e.g. Cl2). Chlorine is then removed from the substrate processing region. A carbon-and-nitrogen-containing precursor (e.g. TMEDA) is delivered to the substrate processing region to form volatile metal complexes which desorb from the surface of the metal film. The methods presented remove metal while very slowly removing the other exposed materials. A thin metal oxide layer may be present on the surface of the metal layer, in which case a local plasma from hydrogen may be used to remove the oxygen or amorphize the near surface region, which has been found to increase the overall etch rate.

Abstract: A method of etching exposed silicon oxide on patterned heterogeneous structures is described and includes a gas phase etch using plasma effluents formed in a remote plasma. The remote plasma excites a fluorine-containing precursor in combination with an oxygen-containing precursor. Plasma effluents within the remote plasma are flowed into a substrate processing region where the plasma effluents combine with water vapor or an alcohol. The combination react with the patterned heterogeneous structures to remove an exposed silicon oxide portion faster than a second exposed portion. The inclusion of the oxygen-containing precursor may suppress the second exposed portion etch rate and result in unprecedented silicon oxide etch selectivity.

Abstract: A method of etching exposed silicon oxide on patterned heterogeneous structures is described and includes a gas phase etch using plasma effluents formed in a remote plasma. The remote plasma excites a fluorine-containing precursor in combination with an oxygen-containing precursor. Plasma effluents within the remote plasma are flowed into a substrate processing region where the plasma effluents combine with water vapor or an alcohol. The combination react with the patterned heterogeneous structures to remove an exposed silicon oxide portion faster than an exposed silicon nitride portion. The inclusion of the oxygen-containing precursor may suppress the silicon nitride etch rate and result in unprecedented silicon oxide etch selectivity.

Abstract: Methods of selectively etching aluminum oxide from the surface of a patterned substrate are described. The etch selectively removes aluminum oxide relative to other metal oxides and silicon-containing films such as silicon, polysilicon, silicon oxide, silicon germanium and/or silicon nitride. The methods include exposing aluminum oxide to plasma effluents formed in a remote plasma from a chlorine-containing precursor and a hydrocarbon. A remote plasma is used to excite the precursors and a local plasma is used to further excite the plasma effluents and accelerate ions toward the patterned substrate.

Abstract: Methods of evenly etching tungsten liners from high aspect ratio trenches are described. The methods include a remote plasma etch using plasma effluents formed from a fluorine-containing precursor and a high flow of helium. Plasma effluents from the remote plasma are flowed into a substrate processing region where the plasma effluents react with tungsten coating a patterned substrate having high aspect ratio trenches. The plasmas effluents react with exposed surfaces and evenly remove tungsten from outside the trenches and on the sidewalls of the trenches. The plasma effluents pass through an ion suppression element positioned between the remote plasma and the substrate processing region. Optionally, the methods may include concurrent ion bombardment of the patterned substrate to help remove potentially thicker horizontal tungsten regions, e.g., at the bottom of the trenches or between trenches.

Abstract: A tunable plasma etch process includes generating a plasma in a controlled flow of a source gas including NH3 and NF3 to form a stream of plasma products, controlling a flow of un-activated NH3 that is added to the stream of plasma products to form an etch gas stream; and controlling pressure of the etch gas stream by adjusting at least one of the controlled flow of the source gas and the flow of un-activated NH3 until the pressure is within a tolerance of a desired pressure. An etch rate of at least one of polysilicon and silicon dioxide by the etch gas stream is adjustable by varying a ratio of the controlled flow of the source gas to the flow of un-activated NH3.

Abstract: A method of removing titanium nitride hardmask is described. The hardmask resides above a low-k dielectric layer prior to removal and the low-k dielectric layer retains a relatively low net dielectric constant after the removal process. The low-k dielectric layer may be part of a dual damascene structure having copper at the bottom of the vias. A non-porous carbon layer is deposited prior to the titanium nitride hardmask removal to protect the low-k dielectric layer and the copper. The titanium nitride hardmask is removed with a gas-phase etch using plasma effluents formed in a remote plasma from a fluorine-containing precursor. Plasma effluents within the remote plasma are flowed into a substrate processing region where the plasma effluents react with the titanium nitride.

Abstract: A method of removing titanium nitride hardmask is described. The hardmask resides above a low-k dielectric layer prior to removal and the low-k dielectric layer retains a relatively low net dielectric constant after the removal process. The low-k dielectric layer may be part of a dual damascene structure having copper at the bottom of the vias. A non-porous carbon layer is deposited prior to the titanium nitride hardmask removal to protect the low-k dielectric layer and the copper. The titanium nitride hardmask is removed with a gas-phase etch using plasma effluents formed in a remote plasma from a chlorine-containing precursor. Plasma effluents within the remote plasma are flowed into a substrate processing region where the plasma effluents react with the titanium nitride.

Abstract: Methods of producing V-shaped trenches in crystalline substrates are described. The methods involve processing a patterned substrate with etch masking materials defining each side of exposed silicon (100). The exposed silicon (100) is exposed to remotely-excited halogen-containing precursor including chlorine or bromine. The plasma effluents formed from the halogen-containing precursor preferentially remove silicon from all exposed facets other than silicon (111). Etching the crystalline substrates with the plasma effluents produce at least two silicon (111) facets between two adjacent masking elements. Forming the silicon (111) facets may be accelerated by pretreating the crystalline substrates using a halogen-containing precursor locally excited in a biased plasma to initiate the generation of the trench.