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Abstract The chemical dynamics of the elementary reaction of ground state atomic silicon (Si;3P) with germane (GeH4; X1A1) were unraveled in the gas phase under single collision condition at a collision energy of 11.8±0.3 kJ mol−1exploiting the crossed molecular beams technique contemplated with electronic structure calculations. The reaction follows indirect scattering dynamics and is initiated through an initial barrierless insertion of the silicon atom into one of the four chemically equivalent germanium‐hydrogen bonds forming a triplet collision complex (HSiGeH3;3i1). This intermediate underwent facile intersystem crossing (ISC) to the singlet surface (HSiGeH3;1i1). The latter isomerized via at least three hydrogen atom migrations involving exotic, hydrogen bridged reaction intermediates eventually leading to the H3SiGeH isomeri5. This intermediate could undergo unimolecular decomposition yielding the dibridged butterfly‐structured isomer1p1(Si(μ‐H2)Ge) plus molecular hydrogen through a tight exit transition state. Alternatively, up to two subsequent hydrogen shifts toi6andi7, followed by fragmentation of each of these intermediates, could also form1p1(Si(μ‐H2)Ge) along with molecular hydrogen. The overall non‐adiabatic reaction dynamics provide evidence on the existence of exotic dinuclear hydrides of main group XIV elements, whose carbon analog structures do not exist.
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Approaching Rapid, High‐Resolution, Large‐Area Patterning of Semiconducting Polymers Using Projection Photothermal Lithography
Abstract Patterned semiconductors are essential for the fabrication of nearly all electronic devices. Over the last two decades, semiconducting polymers (SPs) have received enormous attention due to their potential for creating low‐cost flexible electronic devices, while development of scalable patterning methods capable of producing sub‐μm feature sizes has lagged. A novel method for patterning SPs termed Projection Photothermal Lithography (PPL) is presented. A lab scale PPL microscope is built and it is demonstrated that rapid (≈4 cm2h−1) and large single exposure area (≈0.69 mm2) sub‐μm patterns can be obtained optically. Polymer domains are selectively removed via a photo‐induced temperature gradient that enables dissolution. It is hypothesized that commercial‐scale patterning with a throughput of≈5 m2h−1and resolution of<1μm could be realized through optimization of optical components.
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- Award ID(s):
- 1636385
- PAR ID:
- 10445344
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials Technologies
- Volume:
- 7
- Issue:
- 6
- ISSN:
- 2365-709X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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