Structure for reducing wafer leakage currents and plasma processing chamber with structure

Abstract

The invention provides a structure for reducing wafer leakage currents. The structure is arranged in a plasma processing chamber which comprises a base, an electrostatic chuck (ESC) arranged on the surface of the base, a direct-current electrode buried in the ESC and a direct-current power supply connected with the ESC. A wafer to be etched is mounted on the ESC, the structure is current-limiting impedance connected between the output end of the direct-current power supply and the ESC, and the resistance is larger than 1Momega. The invention further provides the plasma processing chamber with the structure. By means of the structure and the plasma processing chamber, the leakage current peak value through the wafer during electrifying of the plasma processing chamber and the leakage current steady-state value through the wafer when electrifying is ended can be effectively reduced, the damage probability of the wafer during etching is reduced apparently, and accordingly, the quality and the performance of a made semiconductor device can be effectively enhanced, and the service life is prolonged.

Description

technical field [0001] The invention relates to the field of plasma processing devices, in particular to a structure capable of reducing the peak value of wafer leakage current and reducing the steady-state value of leakage current, and a plasma processing chamber provided with the structure. Background technique [0002] During the plasma etching process of the wafer, a base is set in the plasma processing chamber, a support on the surface of the base, the support is usually an electrostatic chuck (ESC), and a DC electrode embedded in the electrostatic chuck , and a DC power supply connected to the electrostatic chuck. A wafer to be etched is mounted on the electrostatic chuck. [0003] When etching, first turn on the DC power supply and apply energy to the etching reaction gas (composed of one or more gases) in the plasma processing chamber to excite the gas to form plasma, and in the plasma processing chamber there is Radio frequency (RF) energy, microwave energy, and / o...

AI Technical Summary

Problems solved by technology

[0005] The DC power supply of the commonly used plasma processing chamber at present, at the moment of starting plasma etching, that is, the moment when the DC power supply is powered on, will form a leakage current peak value (spike) passing through the entire series circuit, that is, passing through the wafer. , and usually cause wafer device damage (PID) due to the large peak value of the leakage current; at the same time, during the subsequent plasma etching process after power-on, the leakage current will gradually approach a steady-state value, and the steady-state value The state value will also be maintained at a large current value, and when the leakage current has a large steady state value, it will also increase the damage probability of the wafer device, resulting in a shortened service life of the semiconductor device after fabrication

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