Chalcogenide phase-change thin films used as grayscale photolithography materials.

Chalcogenide phase-change thin films are used in many fields, such as optical information storage and solid-state memory. In this work, we present another application of chalcogenide phase-change thin films, i.e., as grayscale photolithgraphy materials. The grayscale patterns can be directly inscribed on the chalcogenide phase-change thin films by a single process through direct laser writing method. In grayscale photolithography, the laser pulse can induce the formation of bump structure, and the bump height and size can be precisely controlled by changing laser energy. Bumps with different height and size present different optical reflection and transmission spectra, leading to the different gray levels. For example, the continuous-tone grayscale images of lifelike bird and cat are successfully inscribed onto Sb(2)Te(3) chalcogenide phase-change thin films using a home-built laser direct writer, where the expression and appearance of the lifelike bird and cat are fully presented. This work provides a way to fabricate complicated grayscale patterns using laser-induced bump structures onto chalcogenide phase-change thin films, different from current techniques such as photolithography, electron beam lithography, and focused ion beam lithography. The ability to form grayscale patterns of chalcogenide phase-change thin films reveals many potential applications in high-resolution optical images for micro/nano image storage, microartworks, and grayscale photomasks.

[1]  Ai Qun Liu,et al.  Fabrication of phase-change chalcogenide Ge2Sb2Te5 patterns by laser-induced forward transfer. , 2011, Optics express.

[2]  R. Venkatasubramanian,et al.  Thin-film thermoelectric devices with high room-temperature figures of merit , 2001, Nature.

[3]  Matthias Wuttig,et al.  Origin of the optical contrast in phase-change materials. , 2007, Physical review letters.

[4]  Fuxi Gan,et al.  Nonlinear absorption of Sb-based phase change materials due to the weakening of the resonant bond , 2012 .

[5]  Reza Ghodssi,et al.  Investigation of gray-scale technology for large area 3D silicon MEMS structures , 2003 .

[6]  J. Tominaga,et al.  Understanding the phase-change mechanism of rewritable optical media , 2004, Nature materials.

[7]  Masud Mansuripur,et al.  Laser-induced phase transitions of Ge2Sb2Te5 thin films used in optical and electronic data storage and in thermal lithography. , 2010, Optics express.

[8]  Dae-Hwan Kang,et al.  Investigation of the optical and electronic properties of Ge2Sb2Te5 phase change material in its amorphous, cubic, and hexagonal phases , 2005 .

[9]  D. Ielmini,et al.  Modeling of Programming and Read Performance in Phase-Change Memories—Part II: Program Disturb and Mixed-Scaling Approach , 2008, IEEE Transactions on Electron Devices.

[10]  S. Elliott,et al.  Microscopic origin of the fast crystallization ability of Ge-Sb-Te phase-change memory materials. , 2008, Nature materials.

[11]  Selective wet etching of Ge2Sb2Te5 phase-change thin films in thermal lithography with tetramethylammonium , 2011 .

[12]  Zengbo Wang,et al.  Ultrafast-laser-induced parallel phase-change nanolithography , 2006 .

[13]  Jhantu Kumar Saha,et al.  Concept to devices: from plasmonic light trapping to upscaled plasmonic solar modules [Invited] , 2013 .

[14]  C. Thomas.  The temperature dependence of the non-ohmic current and switching characteristics of a chalcogenide glass , 1976 .

[15]  Qingle Tang.  Dot distribution type of grayscale mask and colorscale photomask for fabrication diffractive and refractive microlens arrays , 2013, Other Conferences.

[16]  C. Peng,et al.  Experimental and theoretical investigations of laser-induced crystallization and amorphization in phase-change optical recording media , 1997 .

[17]  Xi Dai,et al.  Topological insulators in Bi 2 Se 3 , Bi 2 Te 3 and Sb 2 Te 3 with a single Dirac cone on the surface , 2009 .

[18]  Minseok S. Kim,et al.  Fabricating a multi-level barrier-integrated microfluidic device using grey-scale photolithography , 2013 .

[19]  Yongyou Geng,et al.  Nano-optical information storage induced by the nonlinear saturable absorption effect. , 2011, Nanoscale.

[20]  Stefan Blügel,et al.  Unravelling the interplay of local structure and physical properties in phase-change materials , 2006 .

[21]  Xi Dai,et al.  Topological insulators in Bi2Se3, Bi2Te3 and Sb2Te3 with a single Dirac cone on the surface , 2009 .

[22]  Harukazu Miyamoto,et al.  Nanosize fabrication using etching of phase-change recording films , 2004 .

[23]  Jingsong Wei,et al.  Subwavelength direct laser writing by strong optical nonlinear absorption and melt-ablation threshold characteristics , 2009 .

[24]  P. K. Tan,et al.  Study of the Partial Crystallization Properties of Phase-Change Optical Recording Disks , 1999 .

[25]  J W Goodman,et al.  Laser-induced local heating of multilayers. , 1982, Applied optics.

[26]  Jingsong Wei,et al.  Origin of the giant optical nonlinearity of Sb2Te3 phase change materials , 2010 .

[27]  N. Yamada,et al.  Rapid‐phase transitions of GeTe‐Sb2Te3 pseudobinary amorphous thin films for an optical disk memory , 1991 .

[28]  S. Yagi,et al.  Crystallization process of Sb‐Te alloy films for optical storage , 1988 .

[29]  Tomasz Tkaczyk,et al.  Realization of refractive microoptics through grayscale lithographic patterning of photosensitive hybrid glass. , 2004, Optics express.

[30]  Jingsong Wei,et al.  Laser direct writing pattern structures on AgInSbTe phase change thin film , 2011 .

[31]  Qian Liu,et al.  Grayscale photomask fabricated by laser direct writing in metallic nano-films. , 2009, Optics express.

[32]  D. A. Wright.  Thermoelectric Properties of Bismuth Telluride and its Alloys , 1958, Nature.

[33]  S. Ovshinsky.  Reversible Electrical Switching Phenomena in Disordered Structures , 1968 .

[34]  C. Wright,et al.  Models for phase-change of Ge2Sb2Te5 in optical and electrical memory devices , 2004 .

[35]  Masud Mansuripur,et al.  Local electrical characterization of laser-recorded phase-change marks on amorphous Ge2Sb2Te5 thin films. , 2011, Optics express.

[36]  S. Jhi,et al.  Prediction of topological insulating behavior in crystalline Ge-Sb-Te , 2010 .