Advanced Micro Devices Corporation

Globalfoundries Inc.

Heike Salz

Ralf Richter

Matthias Schaller

Kai Frohberg

Carsten Peters

Volker Grimm

Joerg Hohage

Jan Hoentschel

Andy C Wei

Thorsten E Kammler

Matthias Lehr

Robert Seidel

Martin Mazur

Heike Berthold

Sven Mueller

Michael Finken

Jochen Klais

Sylvio Mattick

By integrating a spacer removal process into the sequence for patterning a first stress-inducing material during a dual stress liner approach, the sidewall spacer structure for one type of transistor may be maintained, without requiring additional lithography steps.

Method for selectively removing a spacer in a dual stress liner approach

Scalability of a strain-inducing mechanism on the basis of a stressed dielectric overlayer may be enhanced by forming a single stress-inducing layer in combination with contact trenches, which may shield a significant amount of a non-desired stress component in the complementary transistor, while also providing a strain component in the transistor width direction when the contact material may be provided with a desired internal stress level.

Contact trenches for enhancing stress transfer in closely spaced transistors

In a dual stress liner approach, the surface conditions after the patterning of a first stress-inducing layer may be enhanced by appropriately designing an etch sequence for substantially completely removing an etch stop material, which may be used for the patterning of the second stress-inducing dielectric material, while, in other cases, the etch stop material may be selectively formed after the patterning of the first stress-inducing dielectric material. Hence, the dual stress liner approach may be efficiently applied to semiconductor devices of the 45 nm technology and beyond.

Technique for reducing topography-related irregularities during the patterning of a dielectric material in a contact level of closely spaced transistors

By forming a buffer material above differently stressed contact etch stop layers followed by the deposition of a further stress-inducing material, enhanced overall device performance may be accomplished, wherein an undesired influence of the additional stress-inducing layer may be reduced in device regions, for instance, by removing the additional material or by performing a relaxation implantation process. Furthermore, process uniformity during a patterning sequence for forming contact openings may be enhanced by partially removing the additional stress-inducing layer at an area at which a contact opening is to be formed.

Interlayer dielectric material in a semiconductor device comprising a doublet structure of stressed materials

During the patterning of stressed layers having different types of intrinsic stress, the effects of the deposition of a silicon dioxide based etch indicator material between the first and second dielectric layers may be significantly reduced by a controlled etch on the basis of optical measurement data indicating the etch rate and, thus, the performance of the respective etch process. In other cases, highly efficient etch indicator species may be incorporated into the stressed dielectric layers or may be formed on a surface portion thereof with reduced layer thickness, thereby providing an enhanced endpoint detection signal without creating the negative effects of silicon dioxide based indicator layers. In one illustrative embodiment, a stressed silicon, nitrogen and carbon-containing layer may be combined with a stressed silicon and nitrogen-containing layer, wherein the carbon species provides a prominent endpoint detection signal.

Technique for patterning differently stressed layers formed above transistors by enhanced etch control strategies

By forming an etch control material with increased thickness on a first stressed dielectric layer in a dual stress liner approach, the surface topography may be smoothed prior to the deposition of the second stressed dielectric material, thereby allowing the deposition of an increased amount of stressed material while not contributing to yield loss caused by deposition-related defects.

Stressed interlayer dielectric with reduced probability for void generation in a semiconductor device by using an intermediate etch control layer of increased thickness

During the patterning of respective contact etch stop layers having a different type of intrinsic stress, the deposition of an etch indicator layer between the first and the second contact etch stop layer may be omitted in order to avoid any undue effects of this layer during the subsequent processing. Local removal of the second stressed layer may be performed on the basis of an etch time controlled etch process, which in some aspects may include the provision of an etch indicator material, wherein feed forward and feed back measurement data may be used in an appropriately designed process controller.

Method for reducing etch-induced process uniformities by omitting deposition of an endpoint detection layer during patterning of stressed overlayers in a semiconductor device

By providing additional etch stop layers and/or etch protection layers, a corresponding etch process for forming contact openings for directly connecting polysilicon lines and active areas may be controlled in a highly reliable manner. Consequently, conductive line erosion and/or penetration into extension regions may be significantly reduced, thereby improving the reliability and performance of corresponding semiconductor devices.

Semiconductor device comprising a contact structure with increased etch selectivity

By partially removing an etch stop layer prior to the formation of a first contact etch stop layer, a superior stress transfer mechanism may be provided in an integration scheme for generating strain by means of contact etch stop layers. Thus, a semiconductor device having different types of transistors may be provided, in which a high degree of metal silicide integrity as well as a highly efficient stress transfer mechanism is achieved.

Technique for creating different mechanical strain by forming a contact etch stop layer stack having differently modified intrinsic stress

By performing a plasma treatment for efficiently sealing the surface of a stressed dielectric layer containing silicon nitride, an enhanced performance during the patterning of contact openings may be achieved, since nitrogen-induced resist poisoning may be significantly reduced during the selective patterning of stressed layers of different types of intrinsic stress.

Method for reducing resist poisoning during patterning of silicon nitride layers in a semiconductor device

The present invention provides a technique for forming differently stressed contact etch stop layers, wherein sidewall spacers are removed prior to the formation of the contact etch stop layers. During the partial removal of respective contact etch stop layers, a corresponding etch stop layer regime is used to substantially avoid any unwanted stress-inducing material residuals, thereby significantly enhancing the stress transfer mechanism.

Technique for creating different mechanical strain by a contact etch stop layer stack with an intermediate etch stop layer

By providing an additional silicon dioxide based etch stop layer, a corresponding etch process for forming contact openings for directly connecting polysilicon lines and active areas may be controlled in a highly reliable manner. In another aspect, the etch selectivity of the contact structure may be increased by a modification of the etch behavior of the exposed portion of the contact etch stop layer.

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Radebeul, Germany

Heike Salz