Xenon difluoride gas-phase etching method for barrier layer

Abstract

The invention discloses a xenon difluoride gas-phase etching method for a barrier layer. The method comprises the following steps: (1) spraying xenon difluoride to the surface of an exposed barrier layer; (2) only irradiating the barrier layer on the upper surface of a dielectric layer to increase the etching rate of the barrier layer on the upper surface of the dielectric layer to be higher than that of the barrier layer on the sidewalls of grooves and connecting holes by adopting light beams. According to the method, the barrier layer on the upper surface of the dielectric layer is irradiated by the light beams to increase the etching rate of the barrier layer on the upper surface of the dielectric layer to be higher than that of the barrier layer on the sidewalls of the grooves and the connecting holes, so that the barrier layer on the sidewalls of the grooves and the connecting holes is prevented from being excessively etched, the microcosmic etching uniformity is improved, and better process effects are achieved.

Description

technical field [0001] The invention relates to the technical field of integrated circuit device manufacturing, and more specifically, relates to a method for etching a barrier layer in the gas phase of xenon difluoride. Background technique [0002] As the size of integrated circuit devices continues to shrink, interconnection delays have increasingly become a bottleneck problem restricting the development of integrated circuits. In order to reduce the interconnection delay, in the manufacture of metal interconnection lines of integrated circuit devices, metal copper with a lower resistivity is used instead of aluminum with a higher resistivity to reduce the interconnection resistance, and a low-K dielectric is selected. material to reduce the capacitance between metal interconnect lines. Such as Figure 6 and Figure 7 As shown, the manufacturing process of the metal interconnection generally includes: firstly, forming a low-K dielectric layer 22 on the semiconductor sub...

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Problems solved by technology

Therefore, in order to increase the rate of xenon difluoride gas phase etching, the semiconductor structure will be heated, while the traditional heating method is contact heating, so that the temperature of the entire semiconductor structure is exactly the same, xenon difluoride gas phase etching low K dielectric The barrier layer 23 on the layer 22 and the barrier layer 23 on the sidewall of the trench and the connection hole are the same, which will also cause excessive etching of the barrier layer 23 on the sidewall of the trench and the connection hole

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