Neuromorphic Chip Integrated with an LSI and Amorphous-metal-oxide Semiconductor Thin-film Synapse Devices

Artificial intelligences are promising in future societies, and neural networks are typical technologies with the advantages such as self-organization, self-learning, parallel distributed computing, and fault tolerance, but their size and power consumption are large. Neuromorphic systems are biomimetic systems from the hardware level, with the same advantages as living brains, especially compact size, low power, and robust operation, but some well-known ones are non-optimized systems, so the above benefits are only partially gained, for example, machine learning is processed elsewhere to download fixed parameters. To solve these problems, we are researching neuromorphic systems from various viewpoints. In this study, a neuromorphic chip integrated with an LSI and amorphous-metal-oxide semiconductor (AOS) thin-film synapse devices has been developed. The neuron elements are digital circuit, which are made in an LSI, and the synapse devices are analog devices, which are made of the AOS thin film and directly integrated on the LSI. This is the world's first hybrid chip where neuron elements and synapse devices of different functional semiconductors are integrated, and local autonomous learning is utilized, which becomes possible because the AOS thin film can be deposited without heat treatment and there is no damage to the underneath layer, and has all advantages of neuromorphic systems.

Fabrication of amorphous metal oxide/p-BiVO4 photocathode: understanding the role of entropy for reducing nitrate to ammonia

The controllable design of chemical microenvironment with the expected thermodynamics and kinetics for boosting catalytic activity and selectivity is still challenging. Herein, an amorphous metal oxide (A-MxOy) was employed to...

Scalable High-Speed Hybrid Complementary Integrated Circuits based on Solution-Processed Organic and Amorphous Metal Oxide Semiconductors

Solution-processed single-crystal organic semiconductors (OSCs) and amorphous metal oxide semiconductors (MOSs) are promising for high-mobility, p- and n-channel thin-film transistors (TFTs), respectively. Organic−inorganic hybrid complementary circuits hence have great potential to satisfy practical requirements; however, some chemical incompatibilities between OSCs and MOSs, such as heat and chemical resistance, conventionally make it difficult to rationally integrate TFTs based on solution-processed OSC and MOS into the same substrates. In this work, we achieved a rational integration method based on the solution-processed semiconductors by carefully managing the device configuration and the deposition and patterning techniques from materials point of view. The balanced high performances as well as the uniform fabrication of the TFTs led to densely integrated five-stage ring oscillators with the stage propagation delay of 1.3 µs, which is the fastest operation among ever reported complementary ring oscillators based on solution-processed semiconductors.