Hitachi, Ltd.

Hitachi Device Eng. Co., Ltd.

June Sugiura

Kazuhiro Komori

Hideaki Takahashi

Kenichi Kuroda

Minoru Fukuda

Toshimasa Kihara

Fumio Tsuchiya

Akira Endo

Hisao Katto

Nozomi Horino

Yuji Arakawa

Yoshiharu Takeuchi

Shinji Shimizu

Yasunobu Kosa

Ken Uchida

A semiconductor memory device having wiring formed next to word lines at the extreme ends of the memory cell arrays or next to word lines of the dummy cell arrays, in order to prevent such word lines from breaking or from becoming deformed. The wiring is irrelevant to the circuit operation, but is provided with a fixed potential, and is formed through the steps of forming the word lines. The wiring makes the processing conditions applied to the neighboring word lines the same as the processing conditions applied to other word lines.

Method of making a semiconductor memory device

Semiconductor memory device with additional conductive line to prevent

Disclosed is a semiconductor integrated circuit device which includes first field effect transistors of an LDD structure having a floating gate as memory cells and second field effect transistors of the LDD structure as elements other than the memory cells, and which is used as EPROM. A shallow, low impurity concentration region of the first field effect transistor as a part of its source or drain region has a higher impurity concentration than a shallow, low impurity concentration region of the second field effect transistor as a part of its source or drain region.

Method of making semiconductor device with memory cells and peripheral

Disclosed is a semiconductor integrated circuit device which includes first field effect transistors with an LDD structure having a floating gate in memory cells and second field effect transistors with an LDD structure as elements other than memory cells, and which is used as an EPROM. A shallow, low impurity concentration region of the first field effect transistor as a part of its source or drain region has a higher impurity concentration than a shallow, low impurity concentration region of the second field effect transistor as a part of its source or drain region.

Semiconductor device of an LDD structure having a floating gate

An electrically programmable read only memory is equipped with latch circuits for sequentially introducing series signals which are fed through external terminals. The converter includes sequentially operated switch elements and latch circuits in order to convert the series signals into parallel signals. The thus converter parallel signals are written simultaneously in a memory array via address decoder operated selection switch elements. According to this method, the writing operations into the memory array can be conducted at a high speed even when one writing operation is relatively long as a result of the parallel signal action.

Semiconductor memory

Disclosed is a semiconductor integrated circuit device which includes first field effect transistors of a LDD structure having a floating gate as memory cells and second field effect transistors of the LDD structure as elements other than the memory cells, and which is used as EPROM. A shallow, low impurity concentration region of the first field effect transistor as a part of its source or drain region has a higher impurity concentration than a shallow, low impurity concentration region of the second field effect transistor as a part of its source or drain region.

Semiconductor device and method of producing the same

An electrically programmable read only memory is equipped with latch circuits for sequentially introducing series signals which are fed through external terminals. The converter includes sequentially operated switch elements and latch circuits in order to convert the series signals into parallel signals. The thus converted parallel signals are written simultaneously in a memory array via address decoder operated selection switch elements. According to this method, the writing operations into the memory array can be conducted at a high speed even when one writing operation is relatively long as a result of the parallel signal action.

An electrically programmable read only memory is equipped with latch circuits for sequentially introducing series signals which are fed through external terminals. The converter includes sequentially operated switch elements and latch circuits in order to convert the series signals into parallel signals. The thus converted parallel signals are written simultaneously in a memory array via address decoder operated selection switch elements. According to this method, the writing operations into the memory array can be conducted at a high speed even when one writing operation is relatively long as a result of this parallel signal action.

Disclosed is a semiconductor device, and method of manufacture thereof, the device having a conductive layer formed on a semiconductor substrate, with an insulating layer interposed between the substrate and conductive layer, and wherein a dense insulating layer is disposed at the sides of the conductive layer so as to cover the sides of the insulating layer on the substrate, the dense insulating layer acting to increase retention of charge in the conductive layer. The conductive layer can be the floating gate of a field effect transistor, with a control gate formed on the floating gate via another insulating layer whose sides can also be covered by the dense insulating layer. Such field effect transistor, having the floating gate, can be used as the memory cell of an EPROM, with the charge being the data stored in the cell. A field effect transistor of a peripheral circuit of the EPROM can also have the dense insulating layer applied so as to cover the sides of the gate oxide layer thereof.

Semiconductor device equipped with a field effect transistor having a

Semiconductor memory device with means to prevent word line breakage

A semiconductor integrated circuit device is provided which includes first field effect transistors of an LDD structure having a floating gate as memory cells and second field effect transistors of the LDD structure as elements other than the memory cells. A shallow, low impurity concentration region of the first field effect transistor which is a part of its source or drain region has a higher impurity concentration than a shallow, low impurity concentration region of the second field effect transistor which is a part of its source or drain region. The device is particularly useful in an EPROM arrangement.

Growing community of inventors

Troy, NY, United States of America

June Sugiura