A method of processing a substrate that includes: flowing dioxygen (O.sub.2) and an adsorbate precursor into a plasma processing chamber that is configured to hold the substrate including an organic layer and a patterned etch mask; sustaining an oxygen-rich plasma while flowing the O.sub.2 and the adsorbate precursor, oxygen species from the O.sub.2 and the adsorbate precursor reacting under the oxygen-rich plasma to form an adsorbate; and exposing the substrate to the oxygen-rich plasma to form a recess in the organic layer, where the adsorbate forms a sidewall passivation layer in the recess.

An apparatus for in-situ etching monitoring in a plasma processing chamber includes a continuous wave broadband light source, an illumination system configured to illuminate an area on a substrate with an incident light beam being directed from the continuous wave broadband light source at normal incidence to the substrate, a collection system configured to collect a reflected light beam being reflected from the illuminated area on the substrate, and to direct the reflected light beam to a first light detector, and a controller. The controller is configured to determine a property of the substrate or structures formed thereupon based on a reference light beam and the reflected light beam, and control an etch process based on the determined property. The reference light beam is generated by the illumination system by splitting a portion of the incident light beam and directed to a second light detector.

Plasma processing apparatus and methods are provided. In one example implementation, the plasma processing apparatus includes a processing chamber. The plasma processing apparatus includes a pedestal disposed in the processing chamber. The pedestal is operable to support a workpiece. The plasma processing apparatus includes a plasma chamber disposed above the processing chamber in a vertical direction. The plasma chamber includes a dielectric sidewall. The plasma processing apparatus includes a separation grid separating the processing chamber from the plasma chamber. The plasma processing apparatus includes a first plasma source proximate the dielectric sidewall. The first plasma source is operable to generate a remote plasma in the plasma chamber above the separation grid. The plasma processing apparatus includes a second plasma source. The second plasma source is operable to generate a direct plasma in the processing chamber below the separation grid.

A method of detecting non-uniformity in a plasma in a radio frequency plasma processing system, the method including generating a plasma within a reaction chamber of the radio frequency plasma processing system and detecting electrical signals from the plasma in a frequency range from a frequency of radio frequency power sustaining the plasma to a multiple of about ten times a frequency with a plurality of sensors disposed azimuthally about a chamber symmetry axis of the radio frequency plasma processing system. The method also including comparing the waveforms of the electrical signals picked up from the plasma by the plurality of sensors and determining when a plasma non-uniformity occurs based on the comparing the electrical property of the plasma detected by each of the plurality of sensors.

An apparatus for in-situ etching monitoring in a plasma processing chamber includes a continuous wave broadband light source, an illumination system configured to illuminate an area on a substrate with an incident light beam being directed from the continuous wave broadband light source at normal incidence to the substrate, a collection system configured to collect a reflected light beam being reflected from the illuminated area on the substrate, and to direct the reflected light beam to a first light detector, and a controller. The controller is configured to determine a property of the substrate or structures formed thereupon based on a reference light beam and the reflected light beam, and control an etch process based on the determined property. The reference light beam is generated by the illumination system by splitting a portion of the incident light beam and directed to a second light detector.

A method for etching in plasma processing in a plasma chamber, including continually rotating between a first etch cycle and a second etch cycle for a period of time to etch a feature in a masked substrate. The method including performing the first etch cycle on the masked substrate using a first etching chemistry for a first sub-period. The first etch cycle is continually rotated between a first state configured for passivation, a second state, and third state configured for etching the masked substrate. During the second state of the first etch cycle, a first tuning step is performed by tuning the first etching chemistry, a high frequency RF power and a low frequency RF power to provide extended passivation to the feature in the masked substrate. The method including performing the second etch cycle on the masked substrate using a second etching chemistry for a second sub-period. The second etch cycle is continually rotated between the first state configured for electrical discharge, a fourth state, and the third state configured for etching the feature in the masked substrate. During the fourth state of the second etch cycle, a second tuning step is performed by tuning the second etching chemistry, the high frequency RF power, and the low frequency RF power to provide punch-through etching to the feature in the masked substrate.

A method for fabricating a semiconductor device includes forming a pattern of trenches by etching a first layer formed over an underlying layer of a substrate, each of the trenches having an aspect ratio (AR) in a range with a lower limit of a first AR and an upper limit of a second AR, the pattern including a low-AR trench having the first AR and a high-AR trench having the second AR, the AR of a trench being a ratio of its depth to its opening width, the etching including: executing a first recipe in a plasma chamber to anisotropically etch the first layer for a first duration by flowing etchants through the chamber, an etch rate of the first layer being higher on the low-AR trench relative to that on the high-AR trench; and after executing the first recipe, executing a second recipe in the plasma chamber to etch the first layer anisotropically and concurrently deposit oxygen-containing etch byproducts to passivate exposed portions of sides of the trenches, the etch rate of the first layer being lower on the low-AR trench relative to that on the high-AR trench, wherein executing the second recipe increases a relative oxygen content in the plasma chamber from a first value during the executing of the first recipe to a second value.

An ion-beam etching apparatus includes: a plasma chamber configured to generate plasma from process gas in the plasma chamber; at least one plasma valve coupled to the plasma chamber; an ion-beam source in communication with the plasma chamber, wherein the ion-beam source is configured to extract ions from the plasma and generate ion-beams when a bias is applied to the ion-beam source; an etching chamber in communication with the ion-beam source, and configured to accommodate an object to be etched; at least one etching valve coupled to the etching chamber; and at least one exhausting pump connected to either one or both of the plasma chamber and the etching chamber by the plasma valve and the etching valve, respectively, wherein the at least one exhausting pump is configured to receive and exhaust radicals in either one or both of the plasma chamber and the etching chamber by the plasma valve and the etching valve, respectively.

A method may include generating a plasma in a plasma chamber, the plasma comprising an etchant species and extracting a pulsed ion beam from the plasma chamber and directing the pulsed ion beam to a substrate, where the pulsed ion beam comprises an ON portion and an OFF portion. During the OFF portion the substrate may not be biased with respect to the plasma chamber, and the duration of the OFF portion may be less than a transit time of the etchant species from the plasma chamber to the substrate.

A method may include generating a plasma in a plasma chamber, the plasma comprising an etchant species and extracting a pulsed ion beam from the plasma chamber and directing the pulsed ion beam to a substrate, where the pulsed ion beam comprises an ON portion and an OFF portion. During the OFF portion the substrate may not be biased with respect to the plasma chamber, and the duration of the OFF portion may be less than a transit time of the etchant species from the plasma chamber to the substrate.