Abstract: A substrate is disposed on a substrate holder within a process module. The substrate includes a mask material overlying a target material with at least one portion of the target material exposed through an opening in the mask material. A plasma is generated in exposure to the substrate. For a first duration, a bias voltage is applied at the substrate holder at a first bias voltage setting corresponding to a high bias voltage level. For a second duration, after completion of the first duration, a bias voltage is applied at the substrate holder at a second bias voltage setting corresponding to a low bias voltage level. The second bias voltage setting is greater than 0 V. The first and second durations are repeated in an alternating and successive manner for an overall period of time necessary to remove a required amount of the target material exposed on the substrate.

Abstract: A substrate is disposed on a substrate holder within a process module. The substrate includes a mask material overlying a target material with at least one portion of the target material exposed through an opening in the mask material. A bi-modal process gas composition is supplied to a plasma generation region overlying the substrate. For a first period of time, a first radiofrequency power is applied to the bi-modal process gas composition to generate a plasma to cause etching-dominant effects on the substrate. For a second period of time, after completion of the first period of time, a second radiofrequency power is applied to the bi-modal process gas composition to generate the plasma to cause deposition-dominant effects on the substrate. The first and second radiofrequency powers are applied in an alternating and successive manner for an overall period of time to remove a required amount of exposed target material.

Abstract: For a first period of time, a higher radiofrequency power is applied to generate a plasma in exposure to a substrate, while applying low bias voltage at the substrate level. For a second period of time, a lower radiofrequency power is applied to generate the plasma, while applying high bias voltage at the substrate level. The first and second periods of time are repeated in an alternating and successive manner for an overall period of time necessary to produce a desired effect on the substrate. In some embodiments, the first period of time is shorter than the second period of time such that on a time-averaged basis the plasma has a greater ion density than radical density. In some embodiments, the first period of time is greater than the second period of time such that on a time-averaged basis the plasma has a lower ion density than radical density.

Abstract: Systems and methods for reverse pulsing are described. One of the methods includes receiving a digital signal having a first state and a second state. The method further includes generating a transformer coupled plasma (TCP) radio frequency (RF) pulsed signal having a high state when the digital signal is in the first state and having a low state when the digital signal is in the second state. The method includes providing the TCP RF pulsed signal to one or more coils of a plasma chamber, generating a bias RF pulsed signal having a low state when the digital signal is in the first state and having a high state when the digital signal is in the second state, and providing the bias RF pulsed signal to a chuck of the plasma chamber.

Abstract: A method for forming a stair-step structure in a substrate is provided, wherein the substrate has an organic mask, comprising at least one cycle, wherein each cycle comprises a) depositing a hardmask over the organic mask, b) trimming the organic mask, c) etching the substrate, d) trimming the organic mask, wherein there is no depositing a hardmask between etching the substrate and trimming the organic mask, e) etching the substrate, and f) repeating steps a-e a plurality of times forming the stair-step structure.

Abstract: Methods and apparatus for etching substrates using self-limiting reactions based on removal energy thresholds determined by evaluating the material to be etched and the chemistries used to etch the material involve flow of continuous plasma. Process conditions permit controlled, self-limiting anisotropic etching without alternating between chemistries used to etch material on a substrate. A well-controlled etch front allows a synergistic effect of reactive radicals and inert ions to perform the etching, such that material is etched when the substrate is modified by reactive radicals and removed by inert ions, but not etched when material is modified by reactive radicals but no inert ions are present, or when inert ions are present but material is not modified by reactive radicals.

Abstract: A method for forming a stair-step structure in a substrate is provided, wherein the substrate has an organic mask, comprising at least one cycle, wherein each cycle comprises a) depositing a hardmask over the organic mask, b) trimming the organic mask, c) etching the substrate, d) trimming the organic mask, wherein there is no depositing a hardmask between etching the substrate and trimming the organic mask, e) etching the substrate, and f) repeating steps a-e a plurality of times forming the stair-step structure.

Abstract: Methods for anisotropically etching a tungsten-containing material (such as doped or undoped tungsten metal) include cyclic treatment of tungsten surface with Cl2 plasma and with oxygen-containing radicals. Treatment with chlorine plasma is performed while the substrate is electrically biased resulting in predominant etching of horizontal surfaces on the substrate. Treatment with oxygen-containing radicals passivates the surface of the substrate to etching, and protects the vertical surfaces of the substrate, such as sidewalls of recessed features, from etching. Treatment with Cl2 plasma and with oxygen-containing radicals can be repeated in order to remove a desired amount of material. Anisotropic etching can be performed selectively in a presence of dielectric materials such as silicon oxide, silicon nitride, and silicon oxynitride.

Abstract: A substrate is disposed on a substrate holder within a process module. The substrate includes a mask material overlying a target material with at least one portion of the target material exposed through an opening in the mask material. A bi-modal process gas composition is supplied to a plasma generation region overlying the substrate. For a first period of time, a first radiofrequency power is applied to the bi-modal process gas composition to generate a plasma to cause etching-dominant effects on the substrate. For a second period of time, after completion of the first period of time, a second radiofrequency power is applied to the bi-modal process gas composition to generate the plasma to cause deposition-dominant effects on the substrate. The first and second radiofrequency powers are applied in an alternating and successive manner for an overall period of time to remove a required amount of exposed target material.

Abstract: A method for forming a stair-step structure in a substrate within a plasma processing chamber is provided. An organic mask is formed over the substrate. The organic mask is trimmed with a vertical to lateral ratio of less than 0.8, wherein the trimming simultaneously forms a deposition over the organic mask. The substrate is etched. The steps of trimming the organic mask and etching the substrate are cyclically repeated a plurality of times.

Abstract: A method for forming a stair-step structure in a substrate is provided. An organic mask is formed over the substrate. A hardmask with a top layer and sidewall layer is formed over the organic mask. The sidewall layer of the hard mask is removed while leaving the top layer of the hardmask. The organic mask is trimmed. The substrate is etched. The forming the hardmask, removing the sidewall layer, trimming the organic mask, and etching the substrate are repeated a plurality of times.

Abstract: For a first period of time, a higher radiofrequency power is applied to generate a plasma in exposure to a substrate, while applying low bias voltage at the substrate level. For a second period of time, a lower radiofrequency power is applied to generate the plasma, while applying high bias voltage at the substrate level. The first and second periods of time are repeated in an alternating and successive manner for an overall period of time necessary to produce a desired effect on the substrate. In some embodiments, the first period of time is shorter than the second period of time such that on a time-averaged basis the plasma has a greater ion density than radical density. In some embodiments, the first period of time is greater than the second period of time such that on a time-averaged basis the plasma has a lower ion density than radical density.

Abstract: A substrate is disposed on a substrate holder within a process module. The substrate includes a mask material overlying a target material with at least one portion of the target material exposed through an opening in the mask material. A bi-modal process gas composition is supplied to a plasma generation region overlying the substrate. For a first period of time, a first radiofrequency power is applied to the bi-modal process gas composition to generate a plasma to cause etching-dominant effects on the substrate. For a second period of time, after completion of the first period of time, a second radiofrequency power is applied to the bi-modal process gas composition to generate the plasma to cause deposition-dominant effects on the substrate. The first and second radiofrequency powers are applied in an alternating and successive manner for an overall period of time to remove a required amount of exposed target material.

Abstract: A substrate is disposed on a substrate holder within a process module. The substrate includes a mask material overlying a target material with at least one portion of the target material exposed through an opening in the mask material. A plasma is generated in exposure to the substrate. For a first duration, a bias voltage is applied at the substrate holder at a first bias voltage setting corresponding to a high bias voltage level. For a second duration, after completion of the first duration, a bias voltage is applied at the substrate holder at a second bias voltage setting corresponding to a low bias voltage level. The second bias voltage setting is greater than 0 V. The first and second durations are repeated in an alternating and successive manner for an overall period of time necessary to remove a required amount of the target material exposed on the substrate.

Abstract: Methods for anisotropically etching a tungsten-containing material (such as doped or undoped tungsten metal) include cyclic treatment of tungsten surface with Cl2 plasma and with oxygen-containing radicals. Treatment with chlorine plasma is performed while the substrate is electrically biased resulting in predominant etching of horizontal surfaces on the substrate. Treatment with oxygen-containing radicals passivates the surface of the substrate to etching, and protects the vertical surfaces of the substrate, such as sidewalls of recessed features, from etching. Treatment with Cl2 plasma and with oxygen-containing radicals can be repeated in order to remove a desired amount of material. Anisotropic etching can be performed selectively in a presence of dielectric materials such as silicon oxide, silicon nitride, and silicon oxynitride.

Abstract: A method for etching features with different aspect ratios in an etch layer is provided. A plurality of cycles is provided wherein each cycle comprises a pre-etch transient conditioning of the etch layer, which provides a transient condition of the etch layer, wherein the transient condition has a duration and etching the etch layer for a duration, wherein the duration of the etching with respect to the duration of the transient condition is controlled to control etch aspect ratio dependence.

Abstract: Systems and methods for reverse pulsing are described. One of the methods includes receiving a digital signal having a first state and a second state. The method further includes generating a transformer coupled plasma (TCP) radio frequency (RF) pulsed signal having a high state when the digital signal is in the first state and having a low state when the digital signal is in the second state. The method includes providing the TCP RF pulsed signal to one or more coils of a plasma chamber, generating a bias RF pulsed signal having a low state when the digital signal is in the first state and having a high state when the digital signal is in the second state, and providing the bias RF pulsed signal to a chuck of the plasma chamber.

Abstract: Systems and methods for reverse pulsing are described. One of the methods includes receiving a digital signal having a first state and a second state. The method further includes generating a transformer coupled plasma (TCP) radio frequency (RF) pulsed signal having a high state when the digital signal is in the first state and having a low state when the digital signal is in the second state. The method includes providing the TCP RF pulsed signal to one or more coils of a plasma chamber, generating a bias RF pulsed signal having a low state when the digital signal is in the first state and having a high state when the digital signal is in the second state, and providing the bias RF pulsed signal to a chuck of the plasma chamber.

Abstract: Systems and methods for reverse pulsing are described. One of the methods includes receiving a digital signal having a first state and a second state. The method further includes generating a transformer coupled plasma (TCP) radio frequency (RF) pulsed signal having a high state when the digital signal is in the first state and having a low state when the digital signal is in the second state. The method includes providing the TCP RF pulsed signal to one or more coils of a plasma chamber, generating a bias RF pulsed signal having a low state when the digital signal is in the first state and having a high state when the digital signal is in the second state, and providing the bias RF pulsed signal to a chuck of the plasma chamber.

Abstract: A method for forming a stair-step structure in a substrate is provided. An organic mask is formed over the substrate. A hardmask with a top layer and sidewall layer is formed over the organic mask. The sidewall layer of the hard mask is removed while leaving the top layer of the hardmask. The organic mask is trimmed. The hardmask is removed. The substrate is etched. The forming the hardmask, removing the sidewall layer, trimming the organic mask, and etching the substrate are repeated a plurality of times.