At&t Bell Laboratories

Lucent Technologies Inc.

At&t Ipm Corp.

At+t Corp.

Janmye Sung

Kuo-Hua Lee

Chih-Yuan Lu

Frank M Erceg

Tzu-Yin Chiu

William J Nagy

Te-Yin M Liu

William A Possanza

Michael Allen Prozonic

Thomas Evans Adams

Steven J Hillenius

Kenneth Gordon Moerschel

Larry B Fritzinger

Kenenth G Moerschel

Terry Chrapacz

Francis A Krafty

Yiu M Wong

Duk Y Jeon

A gate contact to a field effect transistor is opened over the source/drain region by forming polysilicon plugs between the gate structure, which has a nitride top layer, and the field oxide regions. The contacts are formed by oxidizing and etching the gate structure and the polysilicon plugs. An oxide layer may be deposited prior to the etching. The latter step opens a gate contact but does not expose the silicon in the plug because the different oxidation rates of the polysilicon plug and the material on top of the gate structure create oxide layers having different thicknesses. The nitride is now removed and contacts formed to the gate structure.

Method for forming self aligned polysilicon contact

A semiconductor integrated circuit structure and method of fabrication is disclosed. The structure includes a FET gate with adjacent double or triple layered gate spacers. The spacers permit precise tailoring of lightly doped drain junction profiles having deep and shallow junction portions. In addition, a self-aligned silicide may be formed solely over the deep junction portion thus producing a reliable low contact resistance connection to source and drain.

FET with gate spacer

A method is provided for optimizing the manufacturing yield of semiconductors. The method provides a backside dielectric layer which protects the semiconductor from electro-static discharge damage during manufacturing. The backside dielectric layer may be a nitride. The backside dielectric layer may be an oxide. The method also provides for optimized ion implantation flood gun current control.

Method for manufacturing gate oxide capacitors including wafer backside

An inductor fabricated for semiconductor use is disclosed. The inductor is formed with a multi-level, multi-element conductor metallization structure which effectively increases conductance throughout the inductor thereby increasing the inductor's Q. The structure of the inductor may also provide for routing the current flowing through the multi-level, multi-element conductors in a way that increases the self inductance between certain conductive elements, thereby increasing the inductor's total inductance.

Inductor for high frequency circuits

An integrated circuit, illustratively an SRAM, having a low resistance path between an access transistor and a pull down transistor is disclosed. Connection for the cell load to the node between the access transistor and pull down transistor is made outside the defined current path.

Memory integrated circuit

An integrated circuit fabrication process for creating field oxide regions in a substrate is disclosed. In the process, masking layers of oxide, nitride and deposited silicon dioxide are formed on the substrate. A pattern that defines the field oxide regions in the substrate is introduced into the substrate through these masking layers. The field oxide region is bordered by steep sidewalls in a portion of the substrate and the masking layers overlying the substrate. A thin layer of oxide is grown on the exposed portion of the substrate, and a conformal second layer of nitride followed by a conformal layer of a polycrystalline material are formed over the substrate/mask structure. The polycrystalline layer is selectively removed, so that the only portion of the polycrystalline material that remains on the structure is the portion covering the sidewalls. The exposed portions of the second nitride layer are then removed, leaving only those portions of the second nitride layer that are interposed between the polycrystalline material and the sidewalls on the substrate surface. The remaining portions of the polycrystalline material on the surface of the structure are then removed. The field oxide is then grown on the field oxide region of the substrate. The portions of the second nitride layer on the sidewalls are lifted and bent as the oxide is grown. The lifting and bending of the second nitride layer forms grooves in the field oxide as it is grown. The remaining layers of the mask are then removed. A thin layer of oxide is then grown or deposited on the surface of the substrate. A layer of nitride with a thickness that is at least one-half the width of the grooves in the field oxide is deposited on the substrate surface. The nitride layer is then removed except for that portion of the nitride in the grooves.

Method for integrated circuit device isolation

A process for fabricating transistors on a substrate is disclosed. In accordance with the process, stacks of material are formed on the surface of the substrate. Walls of silicon dioxide are created around the stacks in order to insulate the material within the stacks from the material deposited outside of the walls. A first layer of polycrystalline material is deposited over the substrate and selectively removed such that only those portions of the polycrystalline layer that surround the stacks of material remain. A layer of silicon nitride or silicon dioxide is then formed over the substrate surface. A first resist is then spun on the substrate surface. This resist aggregates near the stacks of material. An isolation mask is generated that leaves exposed only those areas of the substrate that correspond to the area of overlap between the first polycrystalline area and the stacks of material, which also contain a layer of polycrystalline material. The substrate is then subjected to an etchback process to remove the portion of the polysilicon material that overlaps the material in the stacks.

Process for manufacturing semiconductor BICMOS device

An integrated circuit, illustratively an SRAM, with pull down gates symmetrically positioned with respect to the ground line is disclosed. The symmetric positioning helps to insure cell stability.

Memory integrated circuit with balanced resistance

A semiconductor memory cell with parallel gates is disclosed. The direction of the gates is desirably chosen to minimize lithographic astigmatic effects. Thus gates of comparatively uniform width are produced and predictability of transistor performance thereby improved. Another embodiment of the invention features a connection between two conductive layers and a source/drain. The connection forms a node between one access transistor and one pull-down transistor.

Method of fabricating an integrated circuit with lines of critical width

A semiconductor integrated circuit structure and method of fabrication is disclosed. The structure includes a FET gate with adajcent double or triple-layered gate spacers. The spacers permit precise tailoring of lightly doped drain junction profiles having deep and shallow junction portions. In addition, a self-aligned silicide may be formed solely over the deep junction portion thus producing a reliable low contact resistance connection to source and drain.

A semiconductor memory cell with parallel gates is disclosed. The direction of the gates is desirably chosen to minimize lithographic astigmatic effects. Thus gates of comparatively uniform width are produced and predictability of transistor performance thereby improved. Another embodiment of the invention features a connetion between two conductive layers and a source/drain. The connection forms a node between one access transistor and one pull-down transistor.

Integrated circuit

In the manufacture of integrated-circuit semiconductor devices, prior to formation of a field oxide, a mask structure is provided on a silicon device area, comprising a pad oxide layer, a polysilicon buffer layer, a protective oxide layer, and a silicon nitride mask layer. Inclusion of the protective layer between polysilicon and silicon nitride layers prevents pad oxide failure and attendant substrate etching during strip-etching of the structure overlying the pad oxide.

Integrated-circuit device isolation

When forming a metallization layer in integrated-circuit semiconductor device fabrication, metal such as tungsten, for example, adheres poorly to a dielectric such as, e.g., silicon oxide, and tends to flake off from wafer areas not covered by a glue layer. Processing of the invention prevents such flaking by, first, removing the dielectric from the back side, edge, and 'clip-mark' areas of the wafer and, second, depositing a glue layer on remaining dielectric on the face of the wafer. Removal of dielectric material is by etching in the presence of a protective layer on the face of the wafer.

Metallization processing

Integrated circuits are fabricated with thick self-aligned silicide runners on the field oxide by etching back the first dielectric to expose patterned polysilicon on the field oxide and then forming a silicide on the patterned polysilicon.

Growing community of inventors

Lower Macungie Township, PA, United States of America

Janmye Sung