The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 21, 2001
Filed:
Jan. 21, 2000
San-De Tzu, Taipei, TW;
Wei-Zen Chou, Taipei, TW;
Taiwan Semiconductor Manufacturing Company, Hsin-chu, TW;
Abstract
A method of forming a high transmittance attenuated phase-shifting mask blank, comprising the following steps. An attenuated phase-shifting mask is provided that includes a shifter layer overlying a transparent substrate. The attenuated phase-shifting mask having a first transmittance and an initial phase angle. The attenuated phase-shifting mask and more specifically the shifter layer is treated with an aqueous solution of NH,OH:H,O,for a first predetermined time increasing the first transmittance to a second transmittance and decreasing the initial phase angle to a second phase angle. The attenuated phase-shifting mask is then treated with a selected acid or base for a second predetermined time increasing the second transmittance to a third, predetermined transmittance and increasing the phase angle to a third, predetermined phase angle. The third phase angle is preferably substantially identical to the initial phase angle.