Fujitsu Corporation

Kouji Tsunoda

Tatsuya Usuki

Masao Taguchi

Eiji Yoshida

Nobuyuki Nishikawa

Hiroshi Minakata

Masatoshi Fukuda

A tight contact layer is disposed on a semiconductor substrate, the tight contact layer being made of one material selected from the group consisting of refractory metal, alloy of refractory metal, nitride of refractory metal, and siliconized nitride of refractory metal. An oxide surface layer is disposed on the surface of the tight contact layer, the oxide surface layer being made of oxide of material constituting the tight contact layer. A first conductive layer is disposed on the surface of the oxide surface layer, the first conductive layer being made of a platinum group or alloy which contains a platinum group. When a conductive layer made of metal such as a platinum group is formed on a tight contact layer, coverage and morphology can be prevented from being degraded.

Oxidizing a metal layer for a dielectric having a platinum electrode

A semiconductor device has: an isolation region formed on a semiconductor substrate and defining a continuous active region including a select transistor region and a direct tunnel element region; a gate insulating film formed on a channel region of the select transistor region; a tunnel insulating film formed on a partial area of the direct tunnel element region and having a thickness different from a thickness of the gate insulating film; a continuous floating gate electrode formed above the gate insulating film and the tunnel insulating film; an inter-electrode insulating film formed on a surface of the floating gate electrode; a control gate electrode facing the floating gate electrode via the inter-electrode insulating film; and a pair of source/drain regions formed on both sides of the channel region of the select transistor region and not overlapping the tunnel insulating film.

Direct tunneling memory with separated transistor and tunnel areas

A direct-tunneling semiconductor memory device includes a device isolation structure formed on a semiconductor substrate, including a device isolation trench and a device isolation insulation film filling the device isolation trench, a dielectric film covering both sidewall surfaces and a top surface of a floating gate electrode formed on the semiconductor substrate, a conductive part provided on the sidewall surfaces of the floating gate electrode via the dielectric film, the conductor part constituting a part of a control gate electrode, and first and second diffusion regions formed at respective lateral sides of the floating gate electrode, wherein the first and second diffusion regions are formed on a surface of the device isolation groove with offset from a region right underneath the floating gate electrode, the conductive part is formed in the device region with offset from the device isolation trench.

Direct tunneling semiconductor memory device and fabrication process thereof

Semiconductor device suitable for forming conductive film such as platinum with good coverage, and its manufacture

The semiconductor device comprises a capacitor including a storage electrode, a capacitor dielectric film formed on the storage electrode, and a plate electrode formed on the capacitor dielectric film, the storage electrodehaving an upper end rounded and having a larger thickness at the upper end than a thickness in the rest region. Whereby electric field concentration on the upper end of the storage electrode can be mitigated, and leakage current increase and dielectric breakdown of the capacitor dielectric film can be precluded.

Growing community of inventors

Kawasaki, Japan

Kouji Tsunoda