Abstract:
A structure including an EUV mask and a pellicle attached to the EUV mask. The pellicle includes a pellicle frame and a plurality of pellicle membrane layers attached to the pellicle frame. The plurality of pellicle membrane layers include at least one core pellicle membrane layer and an additional pellicle membrane layer is disposed on the at least one core pellicle membrane layer. In some embodiments, the additional pellicle membrane layer is a material having a thermal emissivity greater than 0.2, a transmittance greater than 80%, and a refractive index (n) for 13.5 nanometer source of greater than 0.9.
Abstract:
A method for fabricating a pellicle includes forming a first dielectric layer over a back surface of a substrate. After forming the first dielectric layer, and in some embodiments, a graphene layer is formed over a front surface of the substrate. In some examples, after forming the graphene layer, the first dielectric layer is patterned to form an opening in the first dielectric layer that exposes a portion of the back surface of the substrate. Thereafter, while using the patterned first dielectric layer as a mask, an etching process may be performed to the back surface of the substrate to form a pellicle having a pellicle membrane that includes the graphene layer.
Abstract:
A method includes inspecting a mask to locate a defect region for a defect of the mask. A phase distribution of an aerial image of the defect region is acquired. A point spread function of an imaging system is determined. One or more repair regions of the mask are identified based on the phase distribution of the aerial image of the defect region and the point spread function. A repair process is performed to the one or more repair regions of the mask to form one or more repair features.
Abstract:
A pellicle structure, a pellicle-mask structure, and a method for forming the pellicle structure are provided. The pellicle structure includes a pellicle film made of a carbon-based material. In addition, the pellicle film is configured to protect a mask structure in a lithography process. The pellicle-mask structure includes a mask substrate having a mask pattern formed over the mask substrate and the pellicle frame disposed on the mask substrate. The pellicle-mask structure further includes the pellicle film disposed on the pellicle frame.
Abstract:
A lithography system for an extreme ultra violet (EUV) mask is provided. The lithography system includes a coupling module. The coupling module includes at least one mask contact element configured to touch a peripheral area of the EUV mask. The lithography system also includes an ammeter having an end electrically connected to the EUV mask through the at least one mask contact element and another end connected to a ground potential. The ammeter includes a sensor configured to measure a current conducting from the EUV mask to the ground potential and a compensation circuit configured to provide a compensation current that is opposite to the current measured by the sensor.
Abstract:
The present disclosure relates to a method of forming an EUV pellicle having an pellicle film connected to a pellicle frame without a supportive mesh, and an associated apparatus. In some embodiments, the method is performed by forming a cleaving plane within a substrate at a position parallel to a top surface of the substrate. A pellicle frame is attached to the top surface of the substrate. The substrate is cleaved along the cleaving plane to form a pellicle film comprising a thinned substrate coupled to the pellicle frame. Prior to cleaving the substrate, the substrate is operated upon to reduce structural damage to the top surface of substrate during formation of the cleaving plane and/or during cleaving the substrate. Reducing structural damage to the top surface of the substrate improves the durability of the thinned substrate and removes a need for a support structure for the pellicle film.
Abstract:
An out-of-band (OoB) suppression layer is applied on a reflective multiplayer (ML) coating, so as to avoid the OoB reflection and to enhance the optical contrast at 13.5 nm. A material having a low reflectivity at wavelength of 193-257 nm, for example, silicon carbide (SiC), is used as the OoB suppression layer. A method of fabricating an EUV mask having the OoB suppression layer and a method of inspecting an EUV mask having the OoB suppression are also provided.
Abstract:
An extreme ultraviolet lithography method is disclosed. In an example, the EUVL method includes forming a resist layer on a substrate; performing a first exposure process to image a first pattern of a first sub-region of a first mask to the resist layer; performing a second exposure process to image a second pattern of a second sub-region of the first mask to the resist layer; and performing a third exposure process to image a third pattern of a first sub-region of a second mask to the resist layer. The second and third patterns are identical to the first pattern. The first, second and third exposure processes collectively form a latent image of the first pattern on the resist layer.
Abstract:
A single-shot metrology for direct inspection of an entirety of the interior of an EUV vessel is provided. An EUV vessel including an inspection tool integrated with the EUV vessel is provided. During an inspection process, the inspection tool is moved into a primary focus region of the EUV vessel. While the inspection tool is disposed at the primary focus region and while providing a substantially uniform and constant light level to an interior of the EUV vessel by way of an illuminator, a panoramic image of an interior of the EUV vessel is captured by way of a single-shot of the inspection tool. Thereafter, a level of tin contamination on a plurality of components of the EUV vessel is quantified based on the panoramic image of the interior of the EUV vessel. The quantified level of contamination is compared to a KPI, and an OCAP may be implemented.
Abstract:
A lithography system includes a radiation source configured to generate an extreme ultraviolet (EUV) light. The lithography system includes a mask that defines one or more features of an integrated circuit (IC). The lithography system includes an illuminator configured to direct the EUV light onto the mask. The mask diffracts the EUV light into a 0-th order ray and a plurality of higher order rays. The lithography system includes a wafer stage configured to secure a wafer that is to be patterned according to the one or more features defined by the mask. The lithography system includes a pupil phase modulator positioned in a pupil plane that is located between the mask and the wafer stage. The pupil phase modulator is configured to change a phase of the 0-th order ray.