Synthesis and characterisation of liquid crystal molecules based on thieno [3,2-b] thiophene and their application in organic field-effect transistors

ABSTRACT

A thieno [3,2-b] thiophene-based planar liquid crystal molecule, C₁₂-PTTT, which possesses the characteristics of an organic field-effect transistor (OFET), was synthesised and its mesomorphic properties were studied by polarising optical microscopy and differential scanning calorimetry. A wide temperature range for a highly oriented smectic phase was observed. OFET devices made under various conditions, such as self-assembled monolayer treatment and alignment treatment, and with micro-channel structures, were fabricated to measure the electrical properties. Among different OFET device conditions, the best electric carrier mobility for C₁₂-PTTT was 0.038 cm² V⁻¹s⁻¹.

GRAPHICAL ABSTRACT

KEYWORDS:

• Alignment layers
• field-effect
• transistors
• liquid crystals
• self-assembled monolayers
• smectic

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the Ministry of Science and Technology of the Republic of China.