Renesas Electronics Corporation

Renesas Technology Corp.

Tsuyoshi Arigane

Digh Hisamoto

Daisuke Okada

Yasuhiro Shimamoto

Takashi Kobayashi

Yoshitaka Sasago

Kan Yasui

Tetsuya Ishimaru

Kenichi Akita

Keisuke Kuwahara

Toshiyuki Mine

Hideaki Kurata

Kazuo Otsuga

Yutaka Okuyama

Yasufumi Morimoto

Hitoshi Kume

Tetsufumi Kawamura

Yoshihiro Ikeda

Kenji Kanamitsu

Yasafumi Morimoto

A first potential and a second potential lower than the first potential are applied to a first end of a memory gate electrode part of the nonvolatile memory and to a second end of the memory gate electrode part, respectively, so that a current is caused to flow in a direction in which the memory gate electrode part extends, then, a hole is injected from the memory gate electrode part into a charge accumulating part below it, therefore, an electron accumulated in the charge accumulating part is eliminated. By causing the current to flow through the memory gate electrode part of a memory cell region as described above, Joule heat can be generated to heat the memory cell. Consequently, in the erasing by a FN tunneling method in which the erasing characteristics degrade at a low temperature, the erasing speed can be improved by heating the memory gate electrode part.

Semiconductor device and method of driving semiconductor device

A memory gate is formed of a first memory gate including a second gate insulating film made of a second insulating film and a first memory gate electrode, and a second memory gate including a third gate insulating film made of a third insulating film and a second memory gate electrode. In addition, the lower surface of the second memory gate electrode is located lower in level than the lower surface of the first memory gate electrode. As a result, during an erase operation, an electric field is concentrated on the corner portion of the first memory gate electrode which is located closer to a selection gate and a semiconductor substrate and on the corner portion of the second memory gate electrode which is located closer to the first memory gate and the semiconductor substrate. This allows easy injection of holes into each of the second and third insulating films.

Semiconductor device and method of manufacturing the same

To provide a semiconductor device having a nonvolatile memory improved in characteristics. In the semiconductor device, a nonvolatile memory has a high-k insulating film (high dielectric constant film) between a control gate electrode portion and a memory gate electrode portion and a transistor of a peripheral circuit region has a high-k/metal configuration. The high-k insulating film arranged between the control gate electrode portion and the memory gate electrode portion relaxes an electric field intensity at the end portion (corner portion) of the memory gate electrode portion on the side of the control gate electrode portion. This results in reduction in uneven distribution of charges in a charge accumulation portion (silicon nitride film) and improvement in erase accuracy.

Semiconductor device and method of manufacturing same

A method and apparatus of forming a nonvolatile semiconductor device including forming a first gate insulating film on a main surface of a first semiconductor region, forming a first gate electrode on the first gate insulating film, forming a second gate insulating film, forming a second gate electrode over a first side surface of the first gate electrode, selectively removing the second gate insulating film, etching the second gate insulating film kept between the second gate electrode and a main surface of the first semiconductor region in order to form an etched charge storage layer, introducing first impurities in the first semiconductor region in a self-aligned manner to the second gate electrode in order to form a second semiconductor region, annealing the semiconductor substrate to extend the second semiconductor region to an area under the second gate electrode.

Nonvolatile semiconductor device and method of manufacturing the same

A charge storage layer interposed between a memory gate electrode and a semiconductor substrate is formed shorter than a gate length of the memory gate electrode or a length of insulating films so as to make the overlapping amount of the charge storage layer and a source region to be less than 40 nm. Therefore, in the write state, since the movement in the transverse direction of the electrons and the holes locally existing in the charge storage layer decreases, the variation of the threshold voltage when holding a high temperature can be reduced. In addition, the effective channel length is made to be 30 nm or less so as to reduce an apparent amount of holes so that coupling of the electrons with the holes in the charge storage layer decreases; therefore, the variation of the threshold voltage when holding at room temperature can be reduced.

Provided is a nonvolatile semiconductor memory device highly integrated and highly reliable. A plurality of memory cells are formed in a plurality of active regions sectioned by a plurality of isolations (silicon oxide films) extending in the Y direction and deeper than a well (p type semiconductor region). In each memory cell, a contact is provided in the well (p type semiconductor region) so as to penetrate through a source diffusion layer (ntype semiconductor region), and the contact that electrically connects bit lines (metal wirings) and the source diffusion layer (ntype semiconductor region) is also electrically connected to the well (p type semiconductor region).

Non-volatile semiconductor memory device and method of manufacturing the same

Nonvolatile semiconductor device including a field effect transistor having a charge storage layer of predetermined length

The semiconductor device includes the nonvolatile memory cell in the main surface of a semiconductor substrate. The nonvolatile memory cell has a first insulating film over the semiconductor substrate, a conductive film, a second insulating film, the charge storage film capable of storing therein charges, a third insulating film over the charge storage film, a first gate electrode, a fourth insulating film in contact with the set of stacked films from the first insulating film to the foregoing first gate electrode, a fifth insulating film juxtaposed with the first insulating film over the foregoing semiconductor substrate, a second gate electrode formed over the fifth insulating film to be adjacent to the foregoing first gate electrode over the side surface of the fourth insulating film, and source/drain regions with the first and second gate electrodes interposed therebetween. The conductive film and the charge storage film are formed to two-dimensionally overlap.

Semiconductor device and manufacturing method thereof

A step is provided between a substrate surface of a select gate and a substrate surface of a memory gate. When the substrate surface of the select gate is lower than the substrate surface of the memory gate, electrons in a channel upon writing obliquely flow in the step portion. Even if the electrons obtain the energy required for passing a barrier during the oblique flow, the electron injection does not occur because electrons are away from the substrate surface. The injection can occur only on a drain region side from a position where the electrons reach the substrate surface. As a result, the injection of the electrons into a gap region is suppressed, so that the electron distribution comes close to the hole distribution. Therefore, variation in a threshold value upon information retention is suppressed, and information-retaining characteristics of a memory cell are improved.

A charge trapping layer in an element isolation region and that in an isolation region between a memory transistor and a selection transistor are removed so that the charges are not injected or trapped in the regions. Also, in an element isolation region, gate electrodes of each memory transistor are united at a position higher than a gate electrode of the selection transistor from a surface of a silicon substrate in an element isolation region, thereby reducing the capacitance between the memory transistor and the selection transistor.

Nonvolatile semiconductor storage device having an element formation region and a plurality of element isolation regions and manufacturing method of the same

Suppressing a leakage current is required in a flash memory because the channel length is made shorter with a reduction in the memory cell size. In an AND type memory array having an assist electrode, although the memory cell area has been reduced by the field isolation using a MOS transistor, leakage current in the channel direction becomes greater with a reduction in the memory cell size, resulting in problems arising like deterioration of programming characteristics, an increase in the current consumption, and reading failure. To achieve the objective, in the present invention, electrical isolation is performed by controlling at least one assist electrode of the assist electrodes wired in parallel to be a negative voltage during program and read operations and by making the semiconductor substrate surface in the vicinity of the aforementioned assist electrode non-conductive.

Semiconductor memory device

A highly-reliable semiconductor device is realized. For example, each memory cell of a nonvolatile memory included in the semiconductor device is configured to include a source and a drain formed in a P-well, a memory node which is formed on the P-well between the source and the drain via a tunnel insulator and is insulated from its periphery, and a control gate formed on the memory node via an interlayer insulator. When a programming operation using channel hot electrons is to be performed in such a configuration, the P-well is put into an electrically floating state.

Semiconductor device

The object of the present invention is to provide a new nonvolatile semiconductor memory device and its manufacturing method for the purpose of miniaturizing a virtual grounding type memory cell based on a three-layer polysilicon gate, enhancing the performance, and boosting the yield. In a memory cell according to the present invention, a floating gate's two end faces perpendicular to a word line and channel are partly placed over the top of a third gate via a dielectric film. The present invention can reduce the memory cell area of a nonvolatile semiconductor memory device, increase the operating speed, and enhances the yield.

Growing community of inventors

Akishima, Japan

Tsuyoshi Arigane