Infineon Technologies Ag

Siemens Aktiengesellschaft

Bernd Goebel

Emmerich Bertagnolli

Franz Hofmann

Till Schloesser

Wolfgang Roesner

Eve Marie Martin

Josef Willer

Harald Seidl

Siegfried Schwarzl

Dirk Manger

Paul-Werner Von Basse

Martin Popp

Jörn Lützen

Barbara Hasler

Rolf Weis

Martin Gutsche

Helmut Klose

Valentin Rosskopf

Dirk Schumann

Andreas Felber

Alfred Kersch

Stefan Slesazeck

Juergen Lindolf

Bernhard Kowalski

Wolfgang Mueller

Werner Steinhögl

Hermann Jacobs

Emmerich Bertagnoll

Memory cells each having a cell capacitor and a cell transistor, which are arranged in a vertical cell structure, are provided in the cell array of a DRAM. By means of a deep implantation or a shallow implantation and subsequent epitaxial growth of silicon, a buried source/drain layer is formed, from which lower source/drain regions of the cell transistors emerge. The upper edge of the buried source/drain layer can be aligned with respect to a lower edge of a gate electrode of the cell transistor and this results in a reduction of a gate/drain capacitance and also a leakage current between the gate electrode and the lower source/drain region. A body connection plate for the connection of the channel regions is applied to the substrate surface and contact holes are introduced into the body connection plate. Upper source/drain regions of the cell transistors are formed by implantation through the contact holes.

DRAM cell array and memory cell arrangement having vertical memory cells and methods for fabricating the same

In a substrate vertical transistor cells are formed and are arranged, in a transistor cell array, row by row in an x direction and column by column in a y direction. Lower source/drain regions of the transistor cells are connected to a common connection plate. Upper source/drain regions of the transistor cells impart a contact connection for instance to a storage capacitor of a DRAM memory cell. Active trenches running between the transistor cells with word lines are formed along the x direction. The word lines form gate electrodes in sections. A potential at the gate electrode controls a conductive channel in an active region arranged in each case between the upper and the lower source/drain connection region. According to the invention, the active regions of adjacent transistor cells are sections of a contiguous layer body and are connected to one another. An accumulation of charge carriers in the active region and floating body effects are avoided without increasing the area requirement of a transistor cell.

Architecture for vertical transistor cells and transistor-controlled memory cells

A vertical memory cell comprises a storage capacitor, the inner electrode of which is formed in a deep trench, and a vertical selector transistor. The selection transistor has an upper source/drain region and a lower source/drain region, which has emerged by outdiffusion of a dopant from the inner electrode. A gate electrode, which in each case controls a current flow between two assigned source/drain regions, is formed, in segments, as a segment of an addressing line arranged row-wise in active trenches. The provision of an auxiliary structure in the active trenches enables the addressing lines to be vertically positioned in the active trenches independently of a depth of the active trenches. Leakage currents which occur in overlap regions of the addressing lines with the inner electrode or the lower source/drain region are reduced.

Architecture and fabrication method of a vertical memory cell

In order to fabricate a semiconductor memory, a trench capacitor is arranged in a first trench. Beside the first trench, a first longitudinal trench and, parallel on the other side of the first trench, a second longitudinal trench are arranged in the substrate. A first spacer word line is arranged in the first longitudinal trench and a second spacer word line is arranged in the second longitudinal trench. There are arranged in the first trench connecting webs between the first spacer word line and the second spacer word line which have a thickness which, in the direction of the first spacer word line, is less than half the width of the first trench in the direction of the first spacer word line.

Semiconductor memory with memory cells comprising a vertical selection transistor and method for fabricating it

An integrated circuit arrangement that has an integrated test structure is provided. The integrated circuit arrangement includes a transistor array having vertical FET selection transistors electrically coupled to storage capacitors of an assigned memory cell array, the storage capacitors being formed vertically into the depth of a substrate in deep trenches. The test structure may enable a plurality of vertical FET selection transistors by a conductive electrode material embedded in an extended deep trench. With a test structure of this type, it is possible to evaluate characteristic values for leakage currents and capacitances at different semiconductor junctions and also between different sections of the integrated circuit arrangement and also to perform reliability stress tests.

Test structure for improved vertical memory arrays

A semiconductor memory cell configuration includes dynamic memory cells respectively having a trench capacitor and a vertical selection transistor, the memory cells being disposed in matrix form, the trench capacitors and the associated vertical selection transistors following one another in each case in the form of rows and/or columns.

Semiconductor memory cell configuration and a method for producing the configuration

A method of producing an integrated circuit having a vertical MOS transistor includes doping a substrate to form a layer adjacent to its surface and forming a lower doped layer serving as the transistor's first source/drain region. The transistor's channel region is formed by doping a central layer above the lower layer. A second source/drain region is formed by doping an upper layer above the central layer. The upper, central and lower layers form a layer sequence having opposed first and second faces. A connecting structure is formed on the first face to electrically connect the channel region and the substrate. The connecting structure laterally adjoins at least the central layer and the lower layer, and extends into the substrate. A gate dielectric and adjacent gate electrode are formed on the second face.

Integrated circuit with vertical transistors

Memory cells each include one transistor and one capacitor. A memory node of the capacitor is disposed in a first indentation, while a gate electrode of the transistor is disposed in a second indentation. An upper source/drain region, a channel region, and a lower source/drain region of the transistor are disposed above one another and each adjoin both a first flank of the first indentation and the second indentation. At least a portion of the first flank is provided with a capacitor dielectric, which in the region of the lower source/drain region has a recess, in which the memory node adjoins the lower source/drain region. The second indentation of a first one of the memory cells can adjoin the memory node that is disposed in the first indentation of a second one of the memory cells. The second indentations can be parts of word line trenches, which extend transversely to insulation trenches. Above the recess, an insulating structure is preferably disposed in the first indentation and adjoins two adjacent ones of the insulation trenches.

DRAM cell configuration whose memory cells can have transistors and capacitors with improved electrical properties

Layers of metallic lines and layers of memory cells are disposed alternately one above the other. The memory cells each have a diode and a memory element connected in series therewith. The memory element has a layer structure with a magnetoresistive effect. The diode has a layer structure containing at least two metal layers and an insulating layer disposed in between. The layer structure of the memory element and the layer structure of the diode are disposed above one another. The metallic lines of a respective one of the layers run parallel to one another. The metallic lines of mutually adjacent layers run transversely with respect to one another.

Memory cell configuration and method for fabricating it

An integrated circuit having at least two vertical MOS transistors, and method for manufacturing same, wherein first source/drain regions of the two vertical MOS transistors are located in an upper region of sidewalls of a trench. A second source/drain region is shared by both MOS transistors and is adjacent at a floor of the trench. Gate electrodes of the MOS transistors that are arranged at the sidewalls of the trench can be individually contacted via parts of a conductive layer that are arranged above the first source/drain regions. In a manufacturing method, such arrangement is made possible by the deposition of a conductive layer of doped polysilicon before the generation of the trench. The area of an MOS transistor can amount to 4F .

Integrated circuit having at least two vertical MOS transistors and method for manufacturing same

A storage cell is described which includes a storage element whose electric resistance represents an information unit and can be influenced by a magnetic field as well as a transistor which when the information is read out allows for the corresponding storage cell to be selected from among the storage cells. To write the information unit, a write line and a bit line are provided which intersect in the area of the storage element and are able to generate the magnetic field. The storage cell is disposed between the bit line and a shared voltage supply connection. The storage cell is disposed between the bit line and the write line and the write line can coincide with a gate line that controls the transistor. The transistor is a planar or vertical transistor. The storage element and the transistor can be positioned next to or on top of each other.

Memory cell configuration in which an electrical resistance of a memory element represents an information item and can be influenced by a magnetic field, and method for fabricating it

An integrated circuit having at least two vertical MOS transistors, and method for manufacturing same, wherein first source/drain regions of the two vertical MOS transistors are located in an upper region of sidewalls of a trench. A second source/drain region is shared by both MOS transistors and is adjacent a floor of the trench. Gate electrodes of the MOS transistors that are arranged at the sidewalls of the trench can be individually contacted via parts of a conductive layer that are arranged above the first source/drain regions. In a manufacturing method, such arrangement is made possible by the deposition of a conductive layer of doped polysilicon before the generation of the trench. The area of an MOS transistor can amount to 4F .

A storage cell has a number of projections of a semiconductor substrate arranged in rows and columns, neighboring rows of the projections being translation-symmetrical in relation to a y-axis which extends parallel to the columns. Each of the projections has at least one first source/drain region of a selection transistor and one channel region arranged below the first source/drain region, which is surrounded by a gate electrode annularly. A storage capacitor is connected between the first source/drain region and a bit line. The bit line as well as the storage capacitor are arranged essentially above the semiconductor substrate. Second source/drain regions of selection transistors are buried in the semiconductor substrate and connected with each other. Word lines can be formed self-justified in the form of adjacent gate electrodes. The projections can be created by etching with only one mask. The storage cell can be produced with an area of 4F , F being the minimal structural size that can be produced in the respective technology.

Method of forming DRAM cell arrangement

The SRAM cell arrangement comprises six MOS transistors per memory cell that are fashioned as vertical transistors. The MOS transistors are arranged at sidewalls of trenches (G,G,G,). Parts of the memory cell such as, for example, gate electrodes (Ga,Ga,) or conductive structures (L,) fashioned as spacer are contacted via adjacent, horizontal, conductive structures (H,) arranged above a surface (O) of a substrate (S). Connections between parts of memory cells ensue via third conductive structures (L,) arranged at the sidewalls of the depressions and word lines (W) via diffusion regions (D,) that are adjacent to the sidewalls of the depressions within the substrate (S), via first bit lines, via second bit lines (B,) or/and via conductive structures (L,L,, L,) that are partially arranged at different height with respect to an axis perpendicular to the surface (O). Contacts (K,) contact a plurality of parts of the MOS transistors simultaneously.

SRAM cell arrangement and method for manufacturing same

An SRAM cell arrangement which includes six MOS transistors per memory cell wherein each transistor is formed as a vertical transistors. The MOS transistors are arranged at sidewalls of trenches. Parts of the memory cell such as, for example, gate electrodes or conductive structures fashioned as spacers are contacted via adjacent, horizontal, conductive structures arranged above a surface of a substrate. Connections between parts of memory cells occur via third conductive structures arranged at the sidewalls of the depressions and word lines via diffusion regions that are adjacent to the sidewalls of the depressions within the substrate, via first bit lines, via second bit lines and/or via conductive structures that are partially arranged at different heights with respect to an axis perpendicular to the surface. Contacts contact a plurality of parts of the MOS transistors simultaneously.

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Dresden, Germany

Bernd Goebel