substrate W, the polishing rate (removal rate) of the edge portion can be controlled by making the pressure (pressing force) of the retainer ring 3 high or low. When the pressurized fluid is supplied to the pressure chambers 22 to 25, the chuck› ing plate 6 receives an upward force. In this embodiment, the pressurized fluid is supplied via the fluid passage 31 into the pressure chamber 21 so as to prevent the chucking plate 6 from being elevated by the force applied from the pressure chambers 22 to 25. 

[0157] Polishing of the substrate Wis thus performed while appropriately adjusting the pressure applied by the head air cylinder 111 to press the retainer ring 3 against the polishing pad 101, the pressures applied by the pressurized airs sup› plied to the pressure chambers 22 to 25 to press the divisional portions of the substrate W against the polishing pad 101, and appropriately adjusting the currents flowing between the divided electrodes 256a to 256c (the first electrode 256) and the conductive film, e.g., copper film, on the surface of the substrate facing the divided electrodes 256a to 256c ( or the voltages to be applied between the divided electrodes 256a to 256c and the conductive film on the surface of the substrate facing the divided electrodes 256a to 256c ). 

[0158] In this embodiment, the polishing head 1 has the pressure chambers 21 to 25 whose internal pressures can be changed independently via the regulators RE2 to RE6 for fine polishing control. Alternatively, it is possible to use a polish› ing head which is not provide with pressure chambers whose internal pressures are independently variable, but is designed to hold ( e.g., attract) a substrate and press the substrate against the polishing surface of the polishing pad 101 uni› formly e.g., at polishing pressure of not more than 70 hPa (about 1 psi). 

[0159] The operations of the substrate processing apparatus will now be described. 

[0160] First, the substrate cassette 204, which stores a large number of substrates W shown in FIG. 1B each having the copper film 907 formed on the surface, is mounted on the loading and unloading stage. One substrate is removed from the substrate cassette 204 by the transfer robot 202 and placed onto the substrate station 206. The transfer robot 208 receives the substrate from the substrate station 206 and, after revers› ing the substrate as necessary, transfers the substrate to the rotary transporter 210. The rotary transporter 210 is then rotated horizontally, and the substrate, supported by the rotary transporter 210, is held by the polishing head 1 of one of the two electrochemical mechanical polishing apparatuses 250. 

[0161] Thereafter, the substrate, held by the polishing head 1, is moved to a polishing position above the polishing table 100. The polishing head 1 is then lowered to press the sub› strate against the polishing surface of the polishing pad 101 at predetermined pressure of not more than 70 hPa (1 psi). While supplying an electrolytic solution to the polishing pad 101, the voltages are applied by the power source 254 between the divided electrodes 256a to 256c (the first electrode 256) and the conductive film of the substrate, i.e. the copper film 907, facing the divided electrodes 256a to 256c to perform polish› ing (first polishing) of the conductive film. Holding of the substrate, e.g., by vacuum attraction, may be released during polishing of the substrate with the polishing pad 101. 

[0162] In the electrochemical mechanical polishing appa› ratus 250, the first polishing is performed so as to remove the conductive film, e.g., the copper film 907 (and the seed film 906), until an average thickness of the remaining conductive 

film is not more than 300 nm and a variation in thickness of the remaining conductive film falls within not more than 150 nm. During polishing of the copper film 907 (and the seed film 906), the film-thickness detection sensor 274, such as an eddy-current sensor, detects an in-plane distribution of the thickness of the copper film 907 (and the seed film 906), and the control section 280 controls and adjusts the polishing pressures to be applied to the divisional portions (press areas) Cl to C4 shown in FIG. 6. The control section280 also adjusts the electric currents flowing ( or voltages applied) between the divided electrodes 256a to 256c and the conductive film, via the variable resistors 268a to 268c of the variable resistance unit 270. The electrochemical mechanical polishing gener› ally causes little damage to interconnects. Therefore, use of the electrochemical mechanical polishing can significantly reduce damage to an interconnect structure of the substrate. For example, the electrochemical mechanical polishing can be used for removing most part of an interconnect metal film formed outside interconnect recesses. Since a portion of the film outside of the interconnect recesses constitutes a major part of a total amount of the film to be removed, use of the electrochemical mechanical polishing can significantly reduce damage to the interconnect structure. 

[0163] A speed of relative movement between the polishing pad 101 and the substrate W may also be controlled. A rota› tional speed of the polishing pad 101 may be controlled, e.g., in a range of 20 to 40 rpm, and a rotational speed of the substrate W may be controlled, e.g., in a range of 50 to 100 rpm. It is possible to rotate the substrate W in an opposite direction to a rotational direction of the polishing pad 101, if necessity. It is also possible to move the substrate W repeat› edly in the radial direction of the polishing pad 101, if neces› sity. 

[0164] After completion of the first polishing in one of the electrochemical mechanical polishing apparatuses 250, the polished surface and the back surface of the substrate are cleaned (rinsed) with a cleaning liquid, e.g., pure water, and then dried, if necessary. The substrate is then transported via the rotary transporter 210 to another of the electrochemical mechanical polishing apparatuses 250, and held by the pol› ishing head 1. In the electrochemical mechanical polishing apparatus 250 which performed the first polishing, on the other hand, conditioning of the polishing surface of the pol› ishing pad 101 with the dresser 218 is performed so as to prepare for the next polishing. 

[0165] In the second polishing, the substrate, held by the polishing head 1, is moved to a polishing position above the polishing table 100. The polishing head 1 is then lowered to press the substrate against the polishing surface of the polish› ing pad 101. While supplying an electrolytic solution to the polishing pad 101, voltages are applied by the power source 254 between the divided electrodes 256a to 256c (the first electrode 256) and the conductive film of the substrate to perform the second polishing of the conductive film which has not been removed by the first polishing. Specifically, the second polishing is performed so as to remove the copper film 907 ( and the seed film 906) remaining on the barrier film 905 to thereby expose the barrier film 905. 

[0166] The electrochemical mechanical polishing appara› tus 250 performs the second polishing under a condition such that the polishing rate of the conductive film is decreased from the center to the periphery of the substrate. With this operation, the barrier film 905, underlying the conductive film, i.e., the copperfilm907 (and seed film 906), is gradually 

