Tokyo Electron Limited

Yukio Koike

Yasushi Aiba

A tungsten layer is formed on the surface of an object to be treated (e.g., a semiconductor wafer), supplying a process gas which includes a material gas of a tungsten fluoride (e.g., WF ) gas and a reducing gas (e.g., H gas) for reducing the material gas. In this case, an intermediate tungsten film forming step is carried out between a nuclear crystalline film forming step of forming a nuclear crystalline film of tungsten on the surface of the object and a main tungsten film forming step of forming a main tungsten film on the nuclear crystalline film. At the intermediate tungsten film forming step, an intermediate tungsten film is formed while the flow ratio of the material gas to the reducing gas is smaller than that at the main tungsten film forming step. Thus, the incubation time T after the deposition of the nuclear crystalline film is removed, so that it is possible to enhance the whole mean deposition rate and to improve the uniformity of the thickness between objects to be processed.

Tungsten layer forming method and laminate structure of tungsten layer

A method of ion implantation of a semiconductor devices to neutralize electrostatic charge stored on a wafer. Neutralizing electrons are supplied to a passage through which a positive ion beam is passed while forming a barrier of negative electrostatic potential between an area in the passage to which the neutralizing electrons are supplied and the wafer. When the positive ion beam is not present in the passage, the potential of the barrier is set lower than the negative potential corresponding to energy held in the neutralizing electrons. When the beam is not passed through the passage, most of the neutralizing electrons cannot cross over the barrier, but when the beam is passed through the passage, most of the electrons can cross over the barrier, following it, to shower over the wafer.

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Yamanashi-ken, Japan

Yukio Koike