Fujitsu Corporation

Fujitsu Quantum Devices Limited

Teruo Yokoyama

Hiroyuki Oguri

Kenji Arimochi

Yasunori Tateno

Eizo Mitani

Junichiro Nikaido

Toshiaki Moriuchi

Shigeru Kuroda

Tsutomu Igarashi

Takeshi Igarashi

Tomonori Ishikawa

Masahisa Suzuki

The impurity concentration contained in a layer on an electron supply layer of a high electron mobility field effect transistor is set in the range of 1&tilde;10 to 1&tilde;10 atoms/cm , or the bandgap of a Schottky layer is set wider than that of the electron supply layer. Otherwise, in the steps of manufacturing the high electron mobility field effect transistor, after a silicon nitride film has been formed on a GaAs buried layer in which a second recess is formed and in a region on the inside of a first recess formed in a GaAs contact layer, the GaAs buried layer is still heated.

Compound semiconductor device and method of manufacturing the same

A field effect transistor has a semiconductor lamination structure, a Schottky contact gate electrode and source/drain ohmic electrodes disposed on both sides of the gate electrode on the lamination structure, source/drain regions disposed under the source/drain electrodes, a channel layer disposed in the lamination structure spaced apart from the principal surface and connecting the source/drain regions, a barrier layer disposed in the lamination structure between the channel layer and the principal surface and having a conduction band edge energy higher than the channel layer, and a pair of impurity doped regions formed in the barrier layer and channel layer continuously with the source/drain regions on both sides of the gate electrode, wherein a carrier density in the barrier layer is lower than a carrier density in the channel layer in the impurity doped region. A filed effect transistor and its manufacture method are provided which can lower the source resistance of the field effect transistor while the gate breakdown voltage is maintained high.

Field effect transistor

The impurity concentration contained in a layer on an electron supply layer of a high electron mobility field effect transistor is set in the range of 1&times;10,to 1&times;10,atoms/cm,, or the bandgap of a Schottky layer is set wider than that of the electron supply layer.

A laminated layer having a layer containing Al (In) and a layer not containing Al (In) alternately laminated one upon another is plasma etched by an etchant gas which can etch both the layers containing and not containing Al (In). An additive gas containing F is added to the etchant gas while a layer not containing Al (In) is etched. When the surface of the layer containing Al (In) is exposed, fluorides are formed on the surface of the layer containing Al (In) and the etching is automatically stopped. An emission peak specific to Al (In) is monitored to detect which layer is presently etched.

Heterojunction compound semiconductor device and method of manufacturing

A compound semiconductor transistor has a structure in which a first insulating film is formed only under a overhang of a gate electrode an upper part of which is formed widely, and a second insulating film for threshold voltage adjustment is formed on the side of a gate electrode and the first insulating film.

Semiconductor device having T-shaped gate electrode

Method for forming MESFET having T-shaped gate electrode

A semiconductor integrated circuit including therein a plurality of active devices comprises a semiconductor substrate, a first buffer layer on the substrate, a second buffer layer provided on the substrate and incorporating therein defects with a concentration level substantially larger than the concentration level of the defects in the first buffer layer; a device layer provided on the second buffer layer and being provided with the active devices, and a plurality of unconductive, device isolation regions formed between the active devices such that the device isolation region extends from an upper surface of the device layer toward the substrate at least beyond a lower surface of the device layer.

Growing community of inventors

Kawasaki, Japan

Teruo Yokoyama