In a method of inspecting an outer surface of a mask pod, a stream of air is directed at a first location of a plurality of locations on the outer surface. One or more particles are removed by the directed stream of air from the first location on the outer surface. Scattered air from the first location of the outer surface is extracted and a number of particles in the extracted scattered air is determined as a sampled number of particles at the first location. The mask pod is moved and the stream of air is directed at other locations of the plurality of locations to determine the sampled number of particles in extracted scattered air at the other locations. A map of the particles on the outer surface of the mask pod is generated based on the sampled number of particles at the plurality of locations.

An exposure tool is configured to remove contaminants and/or prevent contamination of mirrors and/or other optical components included in the exposure tool. In some implementations, the exposure tool is configured to flush and/or otherwise remove contaminants from an illuminator, a projection optics box, and/or one or more other subsystems of the exposure tool using a heated gas such as ozone (O.sub.3) or extra clean dry air (XCDA), among other examples. In some implementations, the exposure tool is configured to provide a gas curtain (or gas wall) that includes hydrogen (H.sub.2) or another type of gas to reduce the likelihood of contaminants reaching the mirrors included in the exposure tool. In this way, the mirrors and one or more other components of the exposure tool are cleaned and maintained in a clean environment in which radiation absorbing contaminants are controlled to increase the performance of the exposure tool.

A metal-containing photoresist film may be deposited on a semiconductor substrate using a dry deposition technique. Unintended metal-containing photoresist material may form on internal surfaces of a process chamber during deposition, bevel and backside cleaning, baking, development, or etch operations. An in situ dry chamber clean may be performed to remove the unintended metal-containing photoresist material by exposure to an etch gas. The dry chamber clean may be performed at elevated temperatures without striking a plasma. In some embodiments, the dry chamber clean may include pumping/purging and conditioning operations.

The present disclosure describes a structure with a controlled polyimide profile and a method for forming such a structure. The method includes depositing, on a substrate, a photoresist containing polyimide and performing a first anneal at a first temperature. The method further includes exposing the photoresist to a radiation source through a photomask having a pattern associated with a shape of a polyimide opening. The method further includes performing a second anneal at a second temperature and removing a portion of the photoresist to form the polyimide opening. The method further includes performing a third anneal at a third temperature and cleaning the polyimide opening by ashing.

A method includes irradiating debris deposited in an extreme ultraviolet (EUV) lithography system with laser, controlling one or more of a wavelength of the laser or power of the laser to selectively vaporize the debris and limit damage to the EUV) lithography system, and removing the vaporized debris.

A collector mirror for an extreme ultraviolet (EUV) light generator includes a first mirror in a vessel, the vessel being configured to receive a material and a laser beam for generating the EUV light, a second mirror surrounding the first mirror, and a detachable third mirror between the first mirror and the second mirror, the third mirror having an inner diameter that is not smaller than an outer diameter of the first mirror, and an outer diameter that is not larger than an inner diameter of the second mirror.

Method of and apparatus for repairing an optical element disposed in a vacuum chamber while the optical element is in the vacuum chamber. An exposed surface of the optical element is exposed to an ion flux generated by an ion source to remove at least some areas of the surface that have been damaged by exposure to the environment within the vacuum chamber. The method and apparatus are especially applicable to repair multilayer mirrors serving as collectors in systems for generating EUV light for use in semiconductor photolithography.

In an embodiment, a method includes: heating a byproduct transport ring of an extreme ultraviolet source, the byproduct transport ring disposed beneath vanes of the extreme ultraviolet source; after heating the byproduct transport ring for a first duration, heating the vanes; after heating the vanes, cooling the vanes; and after cooling the vanes for a second duration, cooling the byproduct transport ring.

Provide are a reticle transfer device and an exposure system. The reticle transfer device includes a bearing member, a light source, a light detector and a controller. The bearing member is configured to bear the reticle, and the light source is configured to emit irradiation light to the reticle and form reflected light. The light detector is configured to obtain the reflected light and generate a light detection signal. The controller is configured to determine whether particulate matter exists on a surface of the reticle based on the light detection signal. The reticle transfer device can determine whether particulate matter exists on the surface of the reticle in real time based on the light detection signal.

An apparatus includes a vacuum chamber, a reflective optical element arranged in the vacuum chamber and configured to reflect an extreme ultra-violet (EUV) light, and a cleaning module positioned in the vacuum chamber. the cleaning module is operable to provide a mitigation gas flowing towards the reflective optical element and provide a hydrogen-containing gas flowing towards the reflective optical element. The mitigation gas mitigates, by chemical reaction, contamination of the reflective optical element.