Typical p-Type Organic Semiconductor Material "Pentacene"

Organic field-effect transistors (OFETs) are promising components for the next-generation electronic devices. They have attracted much attention for their potential as being flexible, thin and light-weight.¹⁾ Pentacene is one of the most typical p-type organic semiconductor materials which has been studied actively in the field of organic electronics.^2,3) We have commercialized "pentacene (1)" sublimed grade and also have studied fabrication and evaluation of OFET devices in our laboratory.

Figure 1. OFET device configuration

Figure 2. Typical OFET characteristics of pentacene devices (transfer curves) (a) bare (b) OTS-treated substrate

Table 1. OFET characteristics of pentacene devices

The field-effect mobility of pentacene was measured using the top-contact thin-film field-effect transistors geometry (Figure 1). The performances of the OFET devices are summarized in Table 1 and Figure 2. All pentacene-based devices exhibited pure typical p-channel field-effect transistor (FET) characteristics under nitrogen conditions. The FET performances were significantly improved by a self-assembled monolayer; the OTS-treated device demonstrated the highest performance with a hole carrier mobility of 1.52 cm²/Vs and an on/off ratio of 1.5 × 10⁷ (Figure 2).