Taiwan Semiconductor Manufacturing Comp. Ltd.

Kai-Shyang You

Harry-Hak-Lay Chuang

Ming Zhu

Sheng-Chen Chung

Wei Cheng Wu

Lee-Wee Teo

Chi-Ju Lee

Bao-Ru Young

Harry Hak-Lay Chuang

Jin-Aun Ng

A method of preventing contact metal from protruding into neighboring gate devices to affect work functions of the neighboring gate devices is provided includes forming a gate structure. Forming the gate structure includes forming a work function layer, and forming a gate metal layer having a void, wherein the work function layer surrounds the gate metal layer. The method further includes forming a contact plug having a contact metal directly on the gate metal layer of the first gate stack, wherein the contact metal protrudes into the void, and the work function layer prevents the contact metal from protruding into a second gate stack.

Methods to stop contact metal from extruding into replacement gates

An integrated circuit arranged on a silicon-on-insulator (SOI) substrate region is provided. The SOI substrate region is made up of a handle wafer region, an oxide layer arranged over the handle wafer region, and a silicon layer arranged over the oxide layer. A recess extends downward from an upper surface of the silicon layer and terminates in the handle wafer region, thereby defining a recessed handle wafer surface and sidewalls extending upwardly from the recessed handle wafer surface to meet the upper surface of the silicon layer. A first semiconductor device is disposed on the recessed handle wafer surface. A second semiconductor device is disposed on the upper surface of the silicon layer.

Recess technique to embed flash memory in SOI technology

The methods and structures described are used to prevent protrusion of contact metal (such as W) horizontally into gate stacks of neighboring devices to affect the work functions of these neighboring devices. The metal gate under contact plugs that are adjacent to devices and share the (or are connected to) metal gate is defined and lined with a work function layer that has good step coverage to prevent contact metal from extruding into gate stacks of neighboring devices. Only modification to the mask layout for the photomask(s) used for removing dummy polysilicon is involved. No additional lithographical operation or mask is needed. Therefore, no modification to the manufacturing processes or additional substrate processing steps (or operations) is involved or required. The benefits of using the methods and structures described above may include increased device yield and performance.

Structures and methods to stop contact metal from extruding into replacement gates

A method includes providing a substrate having a first surface, forming an isolation structure disposed partly in the substrate and having an second surface higher than the first surface by a step height, removing a portion of the isolation structure to form a recess therein having a bottom surface spaced from the first surface by less than the step height, forming a gate structure, and forming a contact engaging the gate structure over the recess. A different aspect involves an apparatus that includes a substrate having a first surface, an isolation structure disposed partly in the substrate and having a second surface higher than the first surface by a step height, a recess extending downwardly from the second surface, the recess having a bottom surface spaced from the first surface by less than the step height, a gate structure, and a contact engaging the gate structure over the recess.

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Jhubei, Taiwan

Kai-Shyang You