Motorola Corporation

Sanjit K Das

Rajeev Bajaj

Janos Farkas

David K Watts

Melissa Freeman

Olubunmi O Adetutu

Subramoney V Iyer

George R Meyer

Jaime A Saravia

Chelsea Dang

Jason Gomez

Lance B Cook

A method of chemical mechanical planarization of a semiconductor device provides a semiconductor device having a device front surface and a device back surface with the device front surface being a top surface of a second metal layer. A first planarizing step planarizes the device front surface with a first medium to expose a device second front surface, where the first medium comprises a first abrasive component and a first chemical solution. A rinsing step then rinses the device back surface with water. A second planarizing step then planarizes the device second front surface with a second medium where the second medium comprises a second abrasive component and a second chemical solution.

Method of chemical mechanical planarization using a water rinse to

A method for forming a copper interconnect on an integrated circuit (IC) begins by forming a dielectric layer (20) having an opening. A tantalum-based barrier layer (21), such as TaN or TaSiN, is formed within the opening in the layer (20). A copper layer (22) is formed over the barrier layer (21). A first CMP process is used to polish the copper (22) to expose portions of the barrier (21). A second CMP process which is different from the first CMP process is then used to polish exposed portions of the layer (21) faster than the dielectric layer (20) or the copper layer (22). After this two-step CMP process, a copper interconnect having a tantalum-based barrier is formed across the integrated circuit substrate (12).

Chemical mechanical polishing (CMP) slurry for polishing copper

Physical properties of alumina particles in a chemical-mechanical polishing slurry delivery loop (28) are measured using a titration technique (44). Examples of the physical properties include crystallographic phase, surface charge, and surface charge density. The physical properties are correlated to a polishing rate (46). Specification limits are generated using the correlated data (482 and 486). The specification limits are used to determine if no adjustments are required to the polishing parameters (484), if adjustments are required to polishing parameters (488) or if the slurry requires replacement (489). This process can be automated and integrated into a conventional chemical-mechanical polishing processing system (20).

Process for forming a semiconductor device

A method for chemical mechanical polishing (CMP) a copper layer (22) begins by forming the copper layer (22). The copper layer (22) is then exposed to a slurry (24). The slurry (24) contains an oxidizing agent such as H.sub.2 O.sub.2, a carboxylate salt such as ammonium citrate, an abrasive slurry such as alumna abrasive, an optional triazole or triazole derivative, and a remaining balance of a solvent such as deionized water. The use of the slurry (24) polishes the copper layer (22) with a high rate of removal whereby pitting and corrosion of the copper layer (22) is reduced and good copper interconnect planarity is achieved. This slurry (24) has good selectivity of copper to oxide, and results in copper devices which have good electrical performance. In addition, disposal of the slurry (24) is not environmentally difficult since the slurry (24) is environmentally sound when compared to other prior art slurries.

Chemical mechanical polishing (CMP) slurry for copper and method of use

A polishing system (10) is used to polish a semiconductor wafer (16) in accordance with the present invention. Polishing system (10) includes a wafer carrier (14) which includes a modulation unit (20). Modulation unit (20) includes a plurality of capacitors made up of a flexible lower plate (22) and a plurality of smaller upper plate segments (24). A controller (40) monitors the capacitance between each smaller upper plate segment (24) and lower plate (22), and compares the measured capacitance against a predefined set capacitance. To the extent the measured capacitance and predefined capacitance are different, controller (40) adjusts the voltage being applied to the respective upper plate segment (24) so that the measured capacitance and predefined capacitance are aligned. Thus, the present invention is able to achieve dynamic and localized control of the shape of the wafer as it is being polished.

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Austin, TX, United States of America

Sanjit K Das