Silicon (Si) has widely been used as an essential material in the modern semiconductor industry. Recently, new attempts have been actively made to apply Si to a variety of fields such as flexible electronic devices and biosensors by manufacturing Si nanomembranes (NMs) having nanometer thickness. In particular, as the thickness of Si is reduced to a nanometer scale, its mechanical, electrical, and optical properties differ from that of its bulk form, which provides opportunities for the development of new conceptual devices. In this review, we present recent advances in Si NM technology that exhibit functional features different from the bulk materials. In addition, we discuss the opportunities and current challenges related to this field.

Physically unclonable crypto primitives have potential applications for anti-counterfeiting, identification, and authentication, which are clone proof and resistant to variously physical attack. Conventional physical unclonable function (PUF) based on Si complementary metal-oxide-semiconductor (CMOS) technologies greatly suffers from entropy loss and bit instability due to noise sensitivity. Here we grow atomically thick MoS₂ thin film and fabricate field-effect transistors (FETs). The inherently physical randomness of MoS₂ transistors from materials growth and device fabrication process makes it appropriate for the application of PUF device. We perform electrical characterizations of MoS₂ FETs, collect the data from 448 devices, and generate PUF keys by splitting drain current at specific levels to evaluate the response performance. Proper selection of splitting threshold enables to generate binary, ternary, and double binary keys. The generated PUF keys exhibit good randomness and uniqueness, providing a possibility for harvesting highly secured PUF devices with two-dimensional materials.