Nanoimprint lithography offers the promise of delivering the lowest Cost of Ownership (CoO) among the competing sub-32nm lithography solutions. The chart below illustrates this with a 22nm node CoO comparison between imprint lithography and its alternatives, referenced to the incumbent 45nm 193i process.
It is clear that imprint provides both a lower fixed and a lower mask cost than other 22nm lithography options.
Lithography fixed costs, which are typically dominated by capital expense, are relatively low for imprint, as expensive precision lenses, mirrors and lasers required by 193nm and EUV are not required. The compact form-factor enables multiple imprint modules to be “clustered” in much the same way as is practiced by etch and deposition tool suppliers, thereby multiplying throughput while sharing common sub-systems among the cluster. Such an approach has been successfully demonstrated with MII’s HD2200 system in the hard disk drive segment. Additionally, imprint systems do not use an expensive resist coat/develop track. Instead, the resist is dispensed from a self-contained module within the process chamber.
Imprint lithography is a highly efficient process: In contrast to the recent need for two 193i lithography passes, the imprint patterning process can be performed in a single pass, regardless of CD, thanks to recent advances in imprint mask pattern fidelity. Additionally, the imprint process is environmentally friendly. With the IntelliJet™ Drop Pattern Generator System, resist waste is reduced dramatically (by >99%) compared with standard track-based systems, while completely eliminating the need for wet developer hardware and chemicals.
Masks represent a significant and rapidly growing cost element in leading-edge lithography. This would also be true for imprint lithography, were it not for the ability to employ mask replication to fabricate many working masks from a single e-beam written “master”. The replication process is particularly valuable in high wafer volume applications such as non-volatile memory or DRAM manufacture. Molecular Imprints currently offers the Perfecta™ Template Replication System for use in hard disk drive patterned media applications and is currently collaborating with Dai Nippon Printing (DNP) to develop and deploy a mask replication infrastructure for the Semiconductor industry.