<title>Surface patterning by pulsed-laser-induced transfer of metals and compounds</title>

Abstract

H-6 720 eg, Dôm tér 9 . , Hungary ABSTRZCT Besults of a systematic study on Q-switched nthy laser induced rrrn2 area transfer of supported titanium and chranium thin films and Ge/Se multilayer structures are reported. The appearance of the prints is governed by film-support adhesion and source-target spacing. Best quality prints are produced by ablating well adhering ntal films in close proximity ( spacing < 15 pm) to the target to be patterned. Transfer fran stacked elenntaxy layers as a source offers a unique possibility of depositing acinpound films by mixing the constituents and transferring the material onto the target substrate in a single step. INTIOJ1JcTIONThe transfer of thin absorbing films from a transparent support onto another target substrate in close proximity with single laser pulses (Laser Induced Forward Transfer = LIFT) offers a straightforward novel approach to surface 1-5,The advantages of this technique are quite obvious : there is no need for cciplicated gas handling and/or vacuiin systems ( in fact all studies reported have been perforrrd in air1or in vacuum5 ) and the propei±ies of the target substrate surface to be patterned have essentially no influence on the process . Although it is anticipated that in the ideal case a spatial resolution approaching the pm danain can be achieved the minflnum lateral dittensions of the patterns actually deposited lie beten 30 and 120 iirn1-5.As a first systematic study of the rather diverse processes involved in thin film ablation and concctnitant deposition by single laser pulses we reporb here on imi2-area processing of supported titanium and chromium thin films . We focus /i / on the role of the glass support film interface in governing the characteristics of both ablation and printing and hi! On tI depennce of irorphology and lateral dirrensions of the transferred patterns on target-source distance . We analyse the elerrentary events by caiiparing experirrental data with calculated temperature distributions in space and tine. The results of a canparative study on Ge/Se bilayer structures allow to clarify the role of the interface in rerroving the absorbing film these also allow to verify the validity of our ablation/deposition rrocèl for fluences not far frau threshold. As a powerful extension we show that LIFT from stacked elementaxy layers on a transparent support as sources offers the unique possibility of positing aaround films by mixing the constituents and transferring the material onto the target substrate in a single step. 2.EXPE REMENTAL'I sets of titanium films the substrates of which were cleaned differently, 150

Laser induced reverse transfer for microfabrication

“…in various specialized applications such as circuit interconnections [7], surface pattering [8], photo mask repair [9], image recordings by transfer of specialized inks [I 0], chip repair technology [11], simultaneous deposition and pattering of high-Tc superconducting films [12], frequency trimming in surface acoustic wave devices [13], and other physical technological aspects [14][15][16][17][18][19]. It is used for fabricating biosensors because it permits to deposit patterns of bio molecules with high spatial resolution [20].…”

Laser induced reverse transfer for microfabrication

“…in various specialized applications such as circuit interconnections [7], surface pattering [8], photo mask repair [9], image recordings by transfer of specialized inks [I 0], chip repair technology [11], simultaneous deposition and pattering of high-Tc superconducting films [12], frequency trimming in surface acoustic wave devices [13], and other physical technological aspects [14][15][16][17][18][19]. It is used for fabricating biosensors because it permits to deposit patterns of bio molecules with high spatial resolution [20].…”

Influence of optical standing waves on the femtosecond laser-induced forward transfer of transparent thin films

“…Note that the electric field in layer 2 is almost identical in the single and multiple film cases except that the reflection coefficient at Γ 23 in eqn. (5), r 23 , is replaced by the effective reflection coefficient between layer 2 and all the subsequent layers, r ′ 23 .…”

“…LIFT has been successfully applied for the direct-writing of metals (e.g., see [1,2,[5][6][7][8][9][10][11]] amongst others), polymers [12], oxides [13,14], superconductors [15], diamond [16], carbon nanotube field emission cathodes [17], conducting polymers [18], and an adenosine triphosphate sensor fabricated from luciferase [19]. Recently, several groups have also investigated the effects of using ultrashort (sub-picosecond) pulses for LIFT (fs-LIFT ) [13,[20][21][22][23][24].…”