Agency: NSF | Branch: Standard Grant | Program: | Phase: | Award Amount: 150.00K | Year: 2010
This Small Business Innovation Research (SBIR) Phase I project aims to develop semiconductor and dielectric inks for thin-film transistor devices to drive Active Matrix organic light-emitting diode (AMOLED) displays. The approach is to employ novel aqueous-based inorganic precursors with low energy barriers to condensation, which will enable the solution deposition of high-quality electronic films that can be cost-effectively scaled to large substrates with uniformity. This project will combine inorganic ink design with flashlamp process for printed electronics to fabricate transistors. It is expected to meet the challenging performance requirements for AMOLED displays on glass with a direct path to low temperature flexible substrates. By tuning the precursor formulation for optimum absorbance and adjusting the flashlamp pulse conditions, the energy required to complete dehydration will be deposited precisely in the film with minimal thermal impact on the substrate.
The broader/commercial impact of this project will be the potential to provide semiconductor and dielectric inks to enable more energy efficient AMOLED displays. AMOLED is the fastest growing segment in display industry. The potential served market for related advanced transistor materials will be about $100 million. The materials and low temperature processes developed in this project will also lay the foundation for much broader applications in inorganic printed electronics and large-area dielectric/optical coatings.
Agency: National Science Foundation | Branch: | Program: SBIR | Phase: Phase I | Award Amount: 100.00K | Year: 2009
This Small Business Innovation Research Phase I project will assess the technical feasibility of developing a robust, high-speed inorganic electron-beam resist platform that will enable the manufacture of electronic devices with feature sizes < 30 nm. The requirements of high speed, low line-width roughness, sufficient etch resistance are extreme for patterning devices at these feature sizes. Success in the project will have a considerable impact on continued progress along the ITRS semiconductor roadmap, which supports several multibillion dollar industries. New levels of device performance will be enabled, providing broad societal impacts through the introduction of advanced electronics, while enhancing prospects for domestic employment in semiconductor manufacturing. The broader scientific and engineering research communities will benefit from new techniques to build novel devices at the extreme end of the nanoscale. This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).
Agency: NSF | Branch: Standard Grant | Program: | Phase: | Award Amount: 1.10M | Year: 2012
This Small Business Innovation Research (SBIR) Phase II project aims to develop spin-coatable liquid precursors for extremely high etch resistance pattern transfer layers (hardmasks) to enable novel devices in advanced integrated circuit manufacturing. The approach is to employ the fully inorganic metal oxide dielectric precursors demonstrated during the Phase I project to provide unparalleled etch selectivity for lithography spin-on hardmask layers. Such materials enable new architectures and deep etches required for future device generations which demand increasingly complex integration of materials to compensate for the limited etch selectivity of conventional organic patterning materials. The expected outcome is one or more inorganic spin-on hardmask materials ready for scale up to manufacturing.
The broader/commercial impact of this project will be the potential to provide materials to improve performance of integrated circuit devices manufactured at dimensions below 22 nm. This project addresses key challenges in the International Technology Roadmap for Semiconductors related to patterning requirements for future high performance electronic devices. The aqueous precursors are synthesized from environmentally benign raw materials, thereby reducing the environmental impact relative to conventional organic materials. The materials and low temperature processes developed in this project will also lay the foundation for broader applications in electronics, energy, and optical coatings.
A bilayer system is used in a simplified process to achieve reduced costs compared with standard fabrication methods that are based on organic photoresists. A major current trend in lithography is the development of exposure tools that have ever-shorter wavelengths, with the overall aim of achieving mass production of devices with sub-10nm feature sizes. Extreme UV lithography (EUVL) at a wavelength of 13.5nm is the main candidate for next-generation lithography technology.1 Highly sensitive resist materials, however, are required for EUVL so that its high-power exposure source requirements can be reduced.2 Until now, chemically amplified resists (CARs) have been used in EUVL.3 CARs are formulated by adding an organic polymer, a photoacid generator, and a quencher species together (see Figure 1). Although such resists have good sensitivity, they also have a number of associated problems. For example, the resolution of chemically amplified resists is strongly affected by pattern collapse, which becomes increasingly important as feature sizes approach the nanometer scale.4 Furthermore, it is challenging to reduce the aspect ratio (film thickness/critical dimension) of CARs because of their high susceptibility to the non-uniform distribution of components in the film. As a result, poor imaging performance tends to be obtained. In our previous work5 we investigated novel materials for use in EUVL, with a particular focus on metal-oxide materials. This class of materials can be formed by small clusters of metal-oxide organic particles without the need for any of the additional molecular species (i.e., organic polymer, photoacid generator, and quencher species) that are normally used for CARs. The metal-oxide resists we use offer a high etch capability for EUVL because of their intrinsic properties,6 and they can therefore serve as a useful alternative to conventional organic films. Compared with CARs (with optimized film thicknesses), the metal-oxide resists offer the advantage of very thin film thicknesses (as low as 20nm), and they minimize the risk of pattern collapse (see Figure 2). The metal-oxide resists can therefore serve as a thin spin-on patternable hard mask for the subsequent etching step in EUVL. Furthermore, the use of a trilayer system is part of the conventional method for transferring a given pattern to a substrate.7 In this conventional approach, a ‘spin-on-glass’ (SOG) is used as the hard mask that is selectively etched with a traditional organic photoresist. In our more recent work,8 however, we have proposed a new, simplified process (see Figure 3) that involves direct exposure of a metal-oxide resist on top of a sacrificial carbon layer (SCL), e.g., spin-on-carbon (SOC). In this way, we eliminate the need for the intermediate SOG hard mask in the patterning stack. The metal-oxide resist we use (obtained from Inpria Corporation) has an etch rate that is about 57 times lower than that of an organic resist (using an oxygen-based chemistry), which enables our process simplification. We have also verified the full ‘lab-to-fab’ (i.e., from laboratory to fabrication) process of our metal-oxide photoresist approach.8, 9 In particular, we integrated the metal-oxide resist into our 7nm back-end process module, a block mask layer for metal patterning with pillar dimensions down to 21nm. We have thus demonstrated (see Figure 4) that our scheme is compatible with manufacturing methods in which standard fabrication equipment is used, and that we can achieve a strong lithographic performance. In another part of our recent work, we investigated the pattern transfer capability of a metal-oxide resist for line-space applications. In this experiment, we used a simplified bilayer stack on a 44nm line-space pitch on top of a silicon oxide layer. We measured the critical dimension (CD) and the CD uniformity of the lines at four different process steps through the opening of the silicon oxide layer. Without any specific process optimization, we were able to transfer the pattern through the final silicon oxide layer. We obtained a CD uniformity of 1.3nm for the fabricated line structures, without a significant impact on the line-width or line-edge roughness (see Figure 5). In summary, we have demonstrated that metal-oxide resists are a valid alternative to conventional organic films in EUV lithography. These materials can thus be used in the patterning process for the fabrication of next-generation high-resolution devices that require EUVL on line-space applications. We have also introduced a simplified bilayer system for the direct exposure of the metal-oxide resist on top of a sacrificial carbon layer. In our future work we will continue to explore the potential patterning applications of these materials. We will also determine the compatibility of such metal-oxide resists for high-volume manufacturing purposes. The authors acknowledge Inpria Corporation for providing the metal-oxide resist and for their technical support.
Agency: NSF | Branch: Standard Grant | Program: | Phase: | Award Amount: 1.10M | Year: 2010
This Small Business Innovation Research (SBIR) Phase II project aims to develop a robust, high-speed inorganic resist platform to revolutionize the manufacture of semiconductor devices with feature sizes < 30 nm. At present, there is no demonstrated organic or inorganic resist that satisfies all of the requirements - high speed, low line-width roughness (LWR), sufficient etch resistance - for patterning devices at these feature sizes. A fundamentally new approach, relying on depositing extremely high-quality oxide films from aqueous solution and very efficient photon-induced network-forming reactions, is being pursued. The approach has enabled the production of extremely small feature sizes and linewidth roughness, enabling optimization within a uniquely high-performance triangle of sensitivity, linewidth roughness, and resolution. Resist deposition, resist formulations, exposure conditions, and processing parameters will be examined in detail to simultaneously address International Technology Roadmap for Semiconductors (ITRS) roadmap requirements for 193i and extreme ultraviolet (EUV) lithography. Anticipated results include 26-nm line/space (L/S) resolution at 3 nm LWR with 193-nm exposures and double patterning, and 22-nm L/S resolution at 1.2 nm LWR with EUV exposures. This resist platform will also lead to a high-resolution electron beam resist with unprecedented sensitivity.
The broader/commercial impact of this project is to develop high-performance resist materials to fill critical unmet needs for semiconductor manufacturing with features smaller than 30 nm. The material being developed addresses two of the ITRS difficult challenges for lithography: an EUV resist that meets 22-nm half-pitch requirements, and the containment of cost escalation of the extension of 193 nm patterning. The resulting product will serve a quickly growing market with a combined opportunity of $250 million in 2015. Success in the project will have a considerable impact on continued productivity gains in the ITRS roadmap, which supports the electronics industry. New levels of device performance will be enabled, providing broad societal impacts through the introduction of advanced electronics, while enhancing prospects for domestic employment in advanced materials and semiconductor manufacturing. The broader scientific and engineering research communities will benefit from new techniques to build and study novel devices at the extreme end of the nanoscale. Finally, solution processing with aqueous materials will reduce the use of toxic solvents and permit a smaller carbon footprint from reduced reliance on vacuum process equipment.