Tokyo Institute of Technology

National Institute for Materials Science

Fuji Electric Corporate Research and Developement Ltd.

Yoshiyuki Yonezawa

Hideomi Koinuma

Yoshinori Konishi

Masashi Kawasaki

Toyohiro Chikyow

Toyohiro Chikyo

Parhat Ahmet

Yoo Young Zo

Jeong-Hwan Song

Young Zo Yoo

A thin film device includes a metal sulfide layer formed on a single crystal silicon substrate by epitaxial growth; and a compound thin film with ionic bonding, which is formed on the metal sulfide layer by epitaxial growth. Alternatively, a thin film device includes a metal sulfide layer formed on a single crystal silicon substrate by epitaxial growth; and at least two compound thin films with ionic bonding, which are formed on the metal sulfide layer by epitaxial growth. For example, (110) surface AlN/MnS/Si (100) thin films formed by successively stacking a MnS layer (about 50 nm thick) and an AlN layer (about 1000 nm thick) on a single crystal Si (100) substrate, are used as a substrate, and a (110) surface GaN layer (about 100 nm thick) operating as a light emitting layer is formed on the substrate, thereby fabricating a thin film device.

Thin film device and its fabrication method

The invention provides a thin film device where ionic crystals are epitaxially grown on a Si single crystal substrate through a proper buffer layer, and its for fabrication method. A ZnS layer is first deposited on a Si single crystal substrate. Ionic crystal thin films (an n-GaN layer, a GaN layer, and a p-GaN layer) are deposited thereon. The ZnS thin film is an oriented film excellent in crystallinity and has excellent surface flatness. When ZnS can be once epitaxially grown on the Si single crystal substrate, the ionic crystal thin films can be easily epitaxially grown subsequently. Therefore, ZnS is formed to be a buffer layer, whereby even ionic crystals having differences in lattice constants from Si can be easily epitaxially grown in an epitaxial thin film with few lattice defects on the Si single crystal substrate. The characteristics of a thin film device utilizing it can be enhanced.

Thin film device

A composite integrated circuit is characterized in that to put an oxide thin film into practical use as an electronic device, a highly crystalline oxide thin film is grown on a silicon substrate. A MOS circuit and a thin film capacitor are formed independently, and the two substrates are laminated using an epoxy resin. They are connected through buried wiring, thereby constituting a composite circuit package. As a second substrate, a (110) plane orientation silicon substrate is used which differs from the IC substrate with a (100) plane. On the (110) silicon substrate after the termination processing, a dielectric layer is film deposited, followed by forming an upper electrode, and by forming a thin film coil. Insulating magnetic gel is filled between coil wires and its upper portion. Thus, the fabrication process of the thin film coil and the composite integrated circuit is completed.

Composite integrated circuit and its fabrication method

Growing community of inventors

Yokosuka, Japan

Yoshiyuki Yonezawa