Photomask

About: Photomask is a research topic. Over the lifetime, 7917 publications have been published within this topic receiving 54524 citations. The topic is also known as: photoreticle & reticle.

Method and apparatus for mask pellicle adhesive residue cleaning

Abstract: Aspects of the invention generally provide methods and apparatus for cleaning adhesive residual on a photomask substrate. In one embodiment, the apparatus includes a processing cell, a support assembly configured to receive a photomask substrate disposed thereon disposed in the processing cell, a protection head assembly disposed above and facing the support assembly, and a head actuator configured to control the elevation of the protection head assembly relative to an upper surface of the support assembly. A cleaning device is provided and positioned to interact with the photomask substrate disposed on the support assembly. In another embodiment, a method of cleaning a periphery region of a photomask substrate includes providing a photomask substrate having a periphery portion and a center portion disposed on a support assembly in a processing cell, lowering a protection cover disposed in the processing cell to cover the center portion of the photomask substrate, providing a brush in the processing cell to clean the periphery portion of the photomask substrate.

Actinic mask imaging: Recent results and future directions from the SHARP EUV Microscope

Abstract: The SEMATECH High Numerical Aperture Actinic Reticle Review Project (SHARP) is a synchrotron-based extreme ultraviolet (EUV) microscope dedicated to photomask research. SHARP has been operational and serving users since June, 2013, and in eight months, SHARP has recorded over 71,000 high-resolution images. Exposure times are 5 to 8 seconds, and 8 or more through-focus series can be collected per hour at positions spanning the entire mask surface. SHARP’s lossless coherence-control illuminator and variable numerical aperture (NA) enable researchers to emulate the imaging properties of both current and future EUV lithography tools. SHARP’s performance continues to improve over time due to tool learning and upgraded capabilities, described here. Within a centered, 3-μm square image region, we demonstrate an illumination power stability above 99%, and an average uniformity of 98.4%. Demonstrations of through-focus imaging with various illumination coherence settings highlight the capabilities of SHARP.

Photomask and method of fabrication thereof

Abstract: A photolithographic mask for use in the fabrication of semiconductor integrated circuit devices, comprising a transparent substrate having a major surface, and a metallic film formed on the major surface of the transparent substrate and impermeable to ultraviolet rays having wavelengths within a predetermined range, wherein the metallic film is doped with sulfur ions to provide a reduced angle of contact between the surface of the film and a body of pure water to achieve an increased degree of adaptability of the photomask to cleaning with pure water when the photomask is put to repeated use over a prolonged period of time.

Methods for etching photolithographic reticles

Abstract: Method and apparatus for etching an optically transparent layer disposed on a substrate, such as a photolithographic reticle, are provided. In one aspect, a method is provided for etching a substrate comprising placing the reticle on a support member in a processing chamber, positioning the reticle on a support member in a processing chamber, wherein the reticle comprises a patterned metal photomask layer formed on an optically transparent material, and a patterned resist material deposited on the patterned metal photomask layer, introducing a processing gas comprising one or more fluorine containing hydrocarbons and one or more chlorine-containing gases into the processing chamber, delivering power to the processing chamber to generate a plasma by applying a source RF power to a coil and applying a bias power to the support member, and etching exposed portions of the optically transparent material.

Impact of 14-nm photomask uncertainties on computational lithography solutions

Abstract: Computational lithography solutions rely upon accurate process models to faithfully represent the imaging system output for a defined set of process and design inputs. These models rely upon the accurate representation of multiple parameters associated with the scanner and the photomask. Many input variables for simulation are based upon designed or recipe-requested values or independent measurements. It is known, however, that certain measurement methodologies, while precise, can have significant inaccuracies. Additionally, there are known errors associated with the representation of certain system parameters. With shrinking total critical dimension (CD) control budgets, appropriate accounting for all sources of error becomes more important, and the cumulative consequence of input errors to the computational lithography model can become significant. In this work, we examine via simulation the impact of errors in the representation of photomask properties including CD bias, corner rounding, refractive index, thickness, and sidewall angle. The factors that are most critical to be accurately represented in the model are cataloged. CD bias values are based on state-of-the-art mask manufacturing data, and other variable changes are speculated, highlighting the need for improved metrology and communication between mask and optical proxmity correction model experts. The simulations are done by ignoring the wafer photoresist model and show the sensitivity of predictions to various model inputs associated with the mask. It is shown that the wafer simulations are very dependent upon the one-dimensional/two-dimensional representation of the mask, and for three-dimensional, the mask sidewall angle is a very sensitive factor influencing simulated wafer CD results.