Fangli Hao

Bio: Fangli Hao is an academic researcher from Lam Research. The author has contributed to research in topics: Plenum space & Vacuum chamber. The author has an hindex of 5, co-authored 10 publications receiving 625 citations.

Gas distribution apparatus for semiconductor processing

Abstract: A gas distribution system for uniformly or non-uniformly distributing gas across the surface of a semiconductor substrate. The gas distribution system includes a support plate and a showerhead which are secured together to define a gas distribution chamber therebetween. A baffle assembly including one or more baffle plates is located within the gas distribution chamber. The baffle arrangement includes a first gas supply supplying process gas to a central portion of the baffle chamber and a second gas supply supplying a second process gas to a peripheral region of the baffle chamber. Because the pressure of the gas is greater at locations closer to the outlets of the first and second gas supplies, the gas pressure at the backside of the showerhead can be made more uniform than in the case with a single gas supply. In one arrangement, the first and second gas supplies open into a plenum between a top baffle plate and a temperature controlled support member wherein the plenum is divided into the central and peripheral regions by an O-ring. In a second arrangement, the first gas supply opens into the central region above an upper baffle plate and the second gas supply opens into the periphery of a plenum between the upper baffle plate and a lower baffle plate.

Deformation reduction at the main chamber

Abstract: A vacuum chamber with a cover with a first section, a second section, and a pocket between the first section and second section is provided. The vacuum chamber has a main cavity to which the first section is adjacent. The vacuum chamber may be used for plasma processing, which may require a critical element to be supported by the first section. The pocket is in fluid communication with the main cavity. When a vacuum is created in the main cavity, the pressure is also reduced in the pocket. As a result, the second section of the cover is deformed by the vacuum in the pocket. However, the vacuum in the pocket helps to prevent the first section from deforming, providing better support for the critical element.

Reaction chamber component having improved temperature uniformity

Abstract: A component useful for a plasma reaction chamber includes a heat sink such as a temperature-controlled support member and a heated member such as an electrically powered showerhead electrode. The showerhead electrode is peripherally secured to the support member to enclose a gas distribution chamber between a top surface of the electrode and a bottom surface of the support member. A heat transfer member extends between the electrode and the support member and transfers heat from an area of temperature buildup on the top surface of the showerhead electrode to the bottom surface of the support member in order to control the temperature distribution across the showerhead electrode.

Linear drive system for use in a plasma processing system

Abstract: A plasma processing system for processing a substrate is disclosed. The system includes a process component capable of effecting a plasma inside a process chamber. The system also includes a gear drive assembly for moving the process component in a linear direction during processing of the substrate.

Wafer area pressure control

Abstract: A plasma processing chamber is provided which provides improved wafer area pressure control. The plasma processing chamber is a vacuum chamber with a device connected for generating and sustaining a plasma. Part of this device would be an etchant gas source and an exhaust port. A confinement ring defines an area above a wafer. The wafer area pressure is dependent on the pressure drop across the confinement ring. The confinement ring is part of a confinement device that provides wafer area pressure control greater than 40 %. Such a confinement device may be a fixed vertical restriction ring in addition to the confinement ring, where the confinement ring is adjustable. In the alternative, three adjustable confinement rings may be used to provide the desired wafer area pressure control.

Substrate Processing Apparatus

Abstract: Process gas discharged from a bypass pipe to a gas exhaust system can be prevented from diffusing back to the inside of a process chamber without having to install a dedicated vacuum pump at the downstream side of the bypass pipe. The substrate processing apparatus includes a process chamber accommodating a substrate, a gas supply system supplying process gas from a process gas source to the process chamber for processing the substrate, a gas exhaust system configured to exhaust the process chamber, two or more vacuum pumps installed in series at the gas exhaust system, and a bypass pipe connected between the gas supply system and the gas exhaust system. The most upstream one of the vacuum pumps is a mechanical booster pump, and the bypass pipe is connected between the mechanical booster pump and the rest vacuum pumps located at a downstream side of the mechanical booster pump.

Apparatus and process for plasma-enhanced atomic layer deposition

Abstract: Embodiments of the invention provide an apparatus configured to form a material during an atomic layer deposition (ALD) process, such as a plasma-enhanced ALD (PE-ALD) process. In one embodiment, a lid assembly for conducting a vapor deposition process within a process chamber is provided which includes an insulation cap and a plasma screen. In one example, the insulation cap has a centralized channel configured to flow a first process gas from an upper surface to an expanded channel and an outer channel configured to flow a second process gas from an upper surface to a groove which is encircling the expanded channel. In one example, the plasma screen has an upper surface containing an inner area with a plurality of holes and an outer area with a plurality of slots. The insulation cap may be positioned on top of the plasma screen to form a centralized gas region with the expanded channel and a circular gas region with the groove.

Plasma uniformity control by gas diffuser hole design

Abstract: Embodiments of a gas diffuser plate for distributing gas in a processing chamber are provided. The gas distribution plate includes a diffuser plate having an upstream side and a downstream side, and a plurality of gas passages passing between the upstream and downstream sides of the diffuser plate. The gas passages include hollow cathode cavities at the downstream side to enhance plasma ionization. The depths, the diameters, the surface area and density of hollow cathode cavities of the gas passages that extend to the downstream end can be gradually increased from the center to the edge of the diffuser plate to improve the film thickness and property uniformity across the substrate. The increasing diameters, depths and surface areas from the center to the edge of the diffuser plate can be created by bending the diffuser plate toward downstream side, followed by machining out the convex downstream side. Bending the diffuser plate can be accomplished by a thermal process or a vacuum process. The increasing diameters, depths and surface areas from the center to the edge of the diffuser plate can also be created computer numerically controlled machining. Diffuser plates with gradually increasing diameters, depths and surface areas of the hollow cathode cavities from the center to the edge of the diffuser plate have been shown to produce improved uniformities of film thickness and film properties.

Lid assembly for a processing system to facilitate sequential deposition techniques

Abstract: A lid assembly for a semiconductor processing system is provided. The lid assembly generally includes a lid having first and second opposed surfaces, a plurality of controllable flow channels extending from the first and second opposed surfaces and a gas control system disposed on the first surface and operably opening and closing the channels. The gas control system includes a gas manifold disposed on the lid, at least one valve coupled to the gas manifold and adapted to control a flow through one of the flow channels, a reservoir fluidly connected to the gas manifold, and a precursor source fluidly connected to the reservoir.

Gas distribution system having fast gas switching capabilities

Abstract: A gas distribution system for supplying different gas compositions to a chamber, such as a plasma processing chamber of a plasma processing apparatus is provided. The gas distribution system can include a gas supply section, a flow control section and a switching section. The gas supply section provides first and second gases, typically gas mixtures, to the flow control section, which controls the flows of the first and second gases to the chamber. The chamber can include multiple zones, and the flow control section can supply the first and second gases to the multiple zones at desired flow ratios of the gases. The gas distribution system can continuously supply the first and second gases to the switching section and the switching section is operable to switch the flows of the first and second gases, such that one of the first and second process gases is supplied to the chamber while the other of the first and second gases is supplied to a by-pass line, and then to switch the gas flows. The switching section preferably includes fast switching valves operable to quickly open and close to allow fast switching of the first and second gases, preferably without the occurrence of undesirable pressure surges or flow instabilities in the flow of either gas.