Well-defined silicon patterns with a high aspect ratio and sharp edges were directly formed by imprinting of liquid silicon which was synthesized via the photopolymerization of cyclopentasilane (CPS: Si5H10) with UV light. After the patterns were formed, they were converted into amorphous silicon patterns by post-annealing at 400 °C. Both dotted and lined patterns whose size ranges from 1 μm to 100 nm were obtained, suggesting that their size could be further reduced. It is very noteworthy that all the obtained patterns demonstrated a good aspect ratio and sharp edges, despite a large shrinkage of 70–80% during the process. By conducting solid-phase crystallization at 800 °C, the pattern portion was converted into polycrystalline pure silicon, whereas the residual film region remained in an amorphous state containing large amounts of oxygen and carbon atoms. Based on the experimental results, the relationship between the decomposition and solidification processes of liquid silicon and its imprinting behavior was clarified and the mechanism of impurity condensation in a residual film region at the annealing temperature of 800 °C and that of well-defined shape formation were discussed. The developed method can be expected to be used in the fabrication of micro-silicon devices because of its production simplicity.

Cyclopentasilane converts into amorphous silicon film between two parallel substrates under atmospheric pressure by thermal decomposition at 350–400 °C, which combines the advantages of high throughput with cost reduction and high quality film formation.

Technologies of device printing have been widely explored, but existing printing techniques still cannot produce well-defined patterns required by fine electronic devices. Here, a new printing method is proposed and the printing of metal-oxide patterns with well-defined shapes was demonstrated. Excellent thin-film transistors with channel lengths around 500 nm were completely printed by this method in an air atmosphere. This printing utilizes a viscoelastic transformation of the precursor gel when imprinted; it softens at a certain temperature during thermal-imprinting so that the gel can be rheologically imprinted. The imprinted pattern shows very small shrinkage during post-annealing, thereby achieving a high shape fidelity to the mould; this results from metal-oxide condensation at imprinting. The viscoelastic transformation and metal-oxide condensation at imprinting constitute the basis for this printing method, which is closely related to the cluster structure in the precursor gel. This method has worked for patterns down to several tens of nanometers.

For generation of a fine aluminum pattern by conventional vacuum processing, it is necessary not only to use complex and costly instruments but also to perform an additional etching process, which may result in physical and chemical damage to the target film surface. Herein we report a simple solution process for the selected deposition of an Al pattern. Al is obtained from the decomposition of alane under dehydrogenation catalysis of a Pt nanocrystalline pattern on a substrate at ∼105–120 °C, while the self-decomposition of alane in solution is avoided in the presence of high-boiling-point amine. This deposited film generates Al crystals with a diameter of several hundred nanometers, following an epitaxial growth to a continual film. The obtained film shows high conductivity, with a resistivity close to that of bulk Al.

In contrast to the traditional chemical vapor deposition technique under high vacuum, we introduce a deposition method in liquid to prepare Pt patterns on substrate near 100 °C by seed growth.

We describe the synthesis of single-crystalline Pt nanocubes with a large diameter (around 35 nm) using a solvent-thermal reaction in a polarity-controlled mixture of 1-butanol, toluene, and N,N-dimethylformamide at 185 °C.

We describe the synthesis of single-crystalline Pt nanocubes with a large diameter (around 35 nm) using a solvent-thermal reaction in a polarity-controlled mixture of 1-butanol, toluene, and N,N-dimethylformamide at 185 °C.

Technologies of device printing have been widely explored, but existing printing techniques still cannot produce well-defined patterns required by fine electronic devices. Here, a new printing method is proposed and the printing of metal-oxide patterns with well-defined shapes was demonstrated. Excellent thin-film transistors with channel lengths around 500 nm were completely printed by this method in an air atmosphere. This printing utilizes a viscoelastic transformation of the precursor gel when imprinted; it softens at a certain temperature during thermal-imprinting so that the gel can be rheologically imprinted. The imprinted pattern shows very small shrinkage during post-annealing, thereby achieving a high shape fidelity to the mould; this results from metal-oxide condensation at imprinting. The viscoelastic transformation and metal-oxide condensation at imprinting constitute the basis for this printing method, which is closely related to the cluster structure in the precursor gel. This method has worked for patterns down to several tens of nanometers.

Well-defined silicon patterns with a high aspect ratio and sharp edges were directly formed by imprinting of liquid silicon which was synthesized via the photopolymerization of cyclopentasilane (CPS: Si5H10) with UV light. After the patterns were formed, they were converted into amorphous silicon patterns by post-annealing at 400 °C. Both dotted and lined patterns whose size ranges from 1 μm to 100 nm were obtained, suggesting that their size could be further reduced. It is very noteworthy that all the obtained patterns demonstrated a good aspect ratio and sharp edges, despite a large shrinkage of 70–80% during the process. By conducting solid-phase crystallization at 800 °C, the pattern portion was converted into polycrystalline pure silicon, whereas the residual film region remained in an amorphous state containing large amounts of oxygen and carbon atoms. Based on the experimental results, the relationship between the decomposition and solidification processes of liquid silicon and its imprinting behavior was clarified and the mechanism of impurity condensation in a residual film region at the annealing temperature of 800 °C and that of well-defined shape formation were discussed. The developed method can be expected to be used in the fabrication of micro-silicon devices because of its production simplicity.

In contrast to the traditional chemical vapor deposition technique under high vacuum, we introduce a deposition method in liquid to prepare Pt patterns on substrate near 100 °C by seed growth.

Cyclopentasilane converts into amorphous silicon film between two parallel substrates under atmospheric pressure by thermal decomposition at 350–400 °C, which combines the advantages of high throughput with cost reduction and high quality film formation.