A system is provided and includes a substrate processing chamber, one or more injectors, and a controller. The one or more injectors inject an electronegative gas, a baseline electropositive gas, and an additional electropositive gas into the substrate processing chamber. The electronegative gas includes an etch precursor. The additional electropositive gas mixes with and increases electron density of a plasma in the substrate processing chamber. The controller is configured to set an amount, flow rate or pressure of the additional electropositive gas based on at least one of a pressure of the electronegative gas or an electron affinity level of the additional electropositive gas.

A charged particle microscope and a method of operating a charged particle microscope are disclosed. The microscope employs a source for producing charged particles, and a source lens below the source to form a charged particle beam which is directed onto a specimen by a condenser system. A detector collects radiation emanating from the specimen in response to irradiation of the specimen by the beam. The source lens is a compound lens, focusing the beam within a vacuum enclosure using both a magnetic lens having permanent magnets outside the enclosure to produce a magnetic field at the beam, and a variable electrostatic lens within the enclosure.

The invention relates to a device for extracting electrical charge carriers from a charge carrier generation chamber with at least one electrode arrangement for extracting charge carriers, wherein the at least one electrode arrangement has at least a first grid electrode and a second grid electrode with corresponding openings. The first and the second grid electrode each contain at least one first electrically conductive grid electrode region, wherein the at least one first grid electrode region of the first grid electrode is configured in a first layer and the at least one first grid electrode region of the second grid electrode is configured in a second layer. The first layer and the second layer are arranged one after the other within the electrode arrangement in the particle emission direction and are spaced from one another by a first distance along the particle emission direction, wherein the at least one first grid electrode region of the first grid electrode forms a first electrically conductive layer portion in the first layer. In addition, a second electrically conductive layer portion, which is electrically insulated from the first layer portion, is configured in the first layer. The second layer portion is formed by at least one second electrically conductive grid electrode region of the first grid electrode or of the second grid electrode, and the second layer portion is electrically conductively connected to the at least one first grid electrode region of the second grid electrode. The device according to the invention for extracting charge carriers thus represents an electrically switchable extraction grid electrode arrangement by the aid of which the beam characteristics of a particle beam of extracted charge carriers can be changed.

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.

An electron beam emitter apparatus includes a light source and a radio frequency (RF) source. In another aspect, an apparatus includes direct density modulation of photo-assisted field emission from a radio frequency cold cathode. A further aspect provides a radio frequency source connected to an electron emitter or cold cathode having tapered projections, and a photon emitter such as a laser, infrared light or ultraviolet light.

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.