Recent progress in 1×x-ray mask technology: Feasibility study using ASET-NIST format TaXN x-ray masks with 100 nm rule 4 Gbit dynamic random access memory test patterns

This article discusses recent progress in 1×x-ray mask technology in Japan. Proximity x-ray lithography (PXL) using synchrotron radiation light with a wavelength of 0.7–1.0 nm can in principle provide as high a throughput as optical lithography, because PXL and optical lithography both employ photon beams and masks. A high-performance electron-beam mask writer called the EB-X3, suitable for PXL, has been developed by NTT under the Association of Super-Advanced Electronics Technologies (ASET) program. It has a reproducible image placement (IP) accuracy of less than 15 nm. We used the shaped-beam EB-X3 to fabricate 100 nm rule x-ray masks for the gate and contact/hole (C/H) layers of 4 Gbit dynamic random access memory (DRAM) test patterns. The ASET-NIST (National Institute of Standards and Technology) type masks consist of a 350-nm-thick TaBN absorber, a 3-μm-thick SiC membrane (27-mm square membrane area), a 1-mm-thick Si substrate, and a 6.63-mm-thick Pyrex glass frame. We have achieved an IP accuracy fo...

[1]  M. Nakaishi,et al.  Effects of X-ray mask structures and processes on X-ray mask distortion , 1990 .

[2]  Mark L. Schattenburg,et al.  Absence of resolution degradation in X-ray lithography for l from 4.5 nm to 0.83 nm , 1990 .

[3]  M. Sugawara,et al.  Smoothing Roughness of SiC Membrane Surface for X-Ray Masks , 1991 .

[4]  Hiroyuki Nagasawa,et al.  Effect of anodic bonding temperature on mechanical distortion of SiC X-ray mask substrate , 1992 .

[5]  Yasuji Matsui,et al.  Total evaluation of W-Ti absorber for x-ray mask , 1994, Advanced Lithography.

[6]  Mark Lawliss,et al.  Overlay enhancement with product‐specific emulation in electron‐beam lithography tools , 1994 .

[7]  S. Uchiyama,et al.  Improving X-Ray Mask Pattern Placement Accuracy by Correcting Process Distortion in Electron Beam Writing. , 1995 .

[8]  Y. Yamashita,et al.  High synchrotron radiation durability microwave plasma chemical vapor deposition diamond x‐ray mask membrane , 1995 .

[9]  Tadahito Matsuda,et al.  Fabrication of 0.2 μm large scale integrated circuits using synchrotron radiation x‐ray lithography , 1995 .

[10]  Y. Yamashita,et al.  Highly Sensitive and Stress-Free Chemically Amplified Negative Working Resist, TDUR-N9, for 0.1 µm Synchrotron Radiation (SR) Lithography , 1996 .

[11]  Y. Yamashita,et al.  X-ray mask distortion induced in back-etching preceding subtractive fabrication : Resist and absorber stress effect , 1996 .

[12]  S. Aya,et al.  An ultralow stress Ta4B absorber for X-ray masks , 1997 .

[13]  Shinji Tsuboi,et al.  Low-stress sputtered chromium–nitride hardmasks for x-ray mask fabrication , 1997 .

[14]  R. Acosta,et al.  Experimental demonstration of the validity of accelerated radiation damage testing of x-ray mask materials , 1998 .

[15]  Takao Taguchi,et al.  Low-dose exposure technique for 100-nm-diam hole replication in x-ray lithography , 1998 .

[16]  Y. Kubota,et al.  Fabrication of x-ray mask from a diamond membrane and its evaluation , 1998 .

[17]  Jerome P. Silverman,et al.  Challenges and progress in x-ray lithography , 1998 .

[18]  S. Kotsuji,et al.  Properties of sputtered TaReGe used as an x-ray mask absorber material , 1998 .

[19]  Yuji Takeda,et al.  XY stage driven by ultrasonic linear motors for the electron-beam x-ray mask writer EB-X3 , 1999 .

[20]  Kenichi Saito,et al.  EB-X3: New electron-beam x-ray mask writer , 1999 .

[21]  Tadashi Sakurai,et al.  Progress in SiC membrane for x-ray mask , 1999, Photomask and Next Generation Lithography Mask Technology.

[22]  Kenichi Saito,et al.  Electron optical system for the x-ray mask writer EB-X3 , 1999 .

[23]  J. Maldonado,et al.  Extension of x-ray lithography to 50 nm with a harder spectrum , 1999 .

[24]  Hajime Aoyama,et al.  Critical-Dimension Controllability of Chemically Amplified Resists for X-Ray Membrane Mask Fabrication. , 2000 .

[25]  Antony J. Bourdillon,et al.  Demagnification by bias in proximity x-ray lithography , 2000, Advanced Lithography.

[26]  Shunichi Uzawa,et al.  Proposal for a 50 nm proximity x-ray lithography system and extension to 35 nm by resist material selection , 2000 .

[27]  Hajime Aoyama,et al.  Precise Delineation Characteristics of Advanced Electron Beam Mask Writer EB-X3 for Fabricating 1× X-Ray Masks , 2000 .

[28]  Hajime Aoyama,et al.  Patterning performance of EB-X3 x-ray mask writer , 2000 .

[29]  Y. Toko,et al.  35.3: Improvement of Transmitted Light Efficiency in SH‐LCDs Using Quarter‐Wave Retardation Films , 2000 .

[30]  Y. Iba,et al.  Amorphous Refractory Compound Film Material for X-Ray Mask Absorbers , 2000 .

[31]  M. Fukuda,et al.  Sub-100 nm device fabrication using proximity X-ray lithography at five levels , 2000, Digest of Papers Microprocesses and Nanotechnology 2000. 2000 International Microprocesses and Nanotechnology Conference (IEEE Cat. No.00EX387).

[32]  Nobutoshi Mizusawa,et al.  Technology and performance of the Canon XRA-1000 production x-ray stepper , 2000 .

[33]  H. Aoyama,et al.  Evaluation of Overlay Accuracy for 100-nm Ground Rule in Proximity X-Ray Lithography , 2000 .

[34]  Hiroshi Watanabe,et al.  Delineation performances of advanced 100-kV EB writer on x-ray membrane mask , 2000, Advanced Lithography.

[35]  Hiroshi Watanabe,et al.  Application of advanced 100-kV EB writer EB-X3 for 100-nm node x-ray mask fabrication , 2001, SPIE Advanced Lithography.