Method and system for improving the manufacturing of metal damascene structures
AssigneeAdvanced Micro Devices, Inc.
InventorsGerd Marxsen, Axel Preusse
Life of this patent
Estimating the term…
Abstract
In a method of in situ controlling the degree of fullness of wide lines in a damascene structure, an optical endpoint detection signal is analyzed so as to determine a time interval of substantially constant signal amplitude. The time interval is then used as a measure of the metal filled in a wide line in a damascene structure. By correlating the length of the time interval to at least one process parameter involved in the formation of the damascene structure, the degree of fullness of lines in the damascene structure may be controlled to maintain within a predefined allowable range.
Claims24
A method for estimating an amount of metal filled in a line in a damascene structure during the chemical mechanical polishing of the structure, the method comprising:
- directing a light beam onto said damascene structure;
- detecting a secondary light beam reflected by the damascene structure;
- determining a first time point indicative of a rising edge and a second time point indicative of a falling edge of an intensity of said secondary light beam;
- and
- estimating, from a time interval defined by the first and second time points, the amount of metal filled in the damascene structure.
A method of controlling the amount of metal in a recessed region of a damascene structure to be formed on a plurality of substrates, the method comprising:
- depositing said metal over a dielectric layer including said recessed region formed on a first substrate;
- removing a portion of said metal by chemical mechanical polishing;
- detecting an optical endpoint signal during the chemical mechanical polishing of the first substrate;
- determining a time interval between a rising edge and a falling edge of said optical endpoint signal;
- and
- controlling at least one process parameter of at least one of the deposition of said metal and the chemical mechanical polishing on the basis of said time interval when processing a second substrate.
A system for estimating the amount of metal filled in a damascene structure, comprising:
- an optical system including a light source adapted to direct a light beam onto a surface of said damascene structure during a chemical mechanical polishing of the damascene structure;
- a detector arranged to receive a secondary light beam reflected from the surface of the damascene structure during the chemical mechanical polishing of the damascene structure and to supply an output signal;
- and
- a control unit connected to receive said output signal of said detector, wherein the control unit is configured to determine a length of a time interval representing a substantially constant output signal strength.
A system for in situ controlling an amount of metal filled in a damascene structure, the system comprising:
- a chemical mechanical polishing tool including an optical endpoint detection system;
- and
- a control unit configured to receive an output signal of said optical end point detection system and to determine a time interval of substantially constant signal amplitude of said output signal and to provide a control signal indicative for a length of said time interval.
Dependencies are inferred from the claim text.