Electroplating Fixtures for Lamp Housing

Embodiments of the present disclosure generally relate to an apparatus used in semiconductor processing. More specifically, embodiments disclosed herein relate to electroplating apparatuses used for components in semiconductor processing chambers.

Rapid thermal processing (RTP) of semiconductor substrates provides a capability for better substrate-to-substrate process repeatability in a single-substrate lamp-heated thermal processing reactor. In semiconductor manufacturing, it is desirable to obtain temperature uniformity over the surface of each substrate during temperature cycling of substrates. Surface temperature uniformity provides uniform process variables (e.g., layer thickness, resistivity and etch depth) for various temperature-activated operations such as film deposition, oxide growth, and annealing. In addition, temperature uniformity is beneficial to prevent thermal stress-induced damage such as warpage, defect generation, and slip.

Radiant heating sources, such as lamps, are used to heat a substrate in the RTP chamber. Lamps are positioned in reflector housings in the RTP chamber. These housings include parts that are coated in metal to increase reflectivity.

Accordingly, there is a need for an improved methods and devices for coating parts in metal to increase reflectivity.

In one embodiment, an electroplating device is provided. The electroplating device includes a housing including a first surface and a second surface and a plurality of holes disposed in the housing. The plurality of holes extend from the first surface to the second surface, and are configured to hold a component to be electroplated. The electroplating device further includes a gas inlet connected to an air bladder. The air bladder is disposed between the plurality of holes. The air bladder is configured to cover an outer surface of the component to be electroplated. The electroplating device further includes a cathode connector disposed below the first surface, and a cathode insert connected to the cathode connector. The cathode insert is connected to the plurality of holes and is configured to electrically charge the component.

In another embodiment, an electroplating device is provided. The electroplating device includes a housing comprising a first surface and a second surface and a plurality of holes disposed in the housing. The plurality of holes extend from the first surface to the second surface. The plurality of holes is configured to hold a component to be electroplated. The electroplating device further includes a plurality of O-rings disposed in the plurality of holes. The O-rings are configured to cover an outer surface of the component. The electroplating device further includes a cathode connector disposed below the first surface, and a cathode insert connected to the cathode connector. The cathode insert is connected to the plurality of holes and is configured to electrically charge the component.

In another embodiment, a method of electroplating a component. The method includes positioning a plurality of components in a plurality of holes of an electroplating device. The plurality of components include an outer surface, an inner surface opposite the outer surface, a top surface, and a bottom surface opposite the top surface. The method further includes sealing the plurality of components in the electroplating device. The outer surface, the top surface, and the bottom surface are covered by the electroplating device. The method further includes submerging the electroplating device in an electrolyte solution, electrically charging the electrolyte solution via a cathode and an anode disposed in the electroplating device, and electroplating the inner surface of the plurality of components.

To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is contemplated that elements and features of one embodiment may be beneficially incorporated in other embodiments without further recitation.

Embodiments of the present disclosure generally relate to an apparatus used in semiconductor processing. More specifically, embodiments disclosed herein relate to electroplating apparatuses used for components in semiconductor processing chambers.

is a cross-sectional view of a reflector housing(e.g. component).is an isometric view of the reflector housing. The reflector housingcontains a first surface, a second surface, an inner surface, and an outer surfaceforming a cylindrical body. The first surfaceis opposite the second surface. The first surfaceand the second surfaceare flat disks. The inner surfaceis opposite the outer surface. The inner surfaceand outer surfaceare cylindrical. The inner surfacehas a first portionand a second portion. The second portionis angled.

The reflector housingis configured to be positioned in a lamp housing. The reflector housingmay be part of a sleeve disposed within a lamp housing. Alternatively, reflector housingmay be an integral part of the lamp housing. The reflector housing reflects light from the lamps towards the processing volume in a processing chamber. The reflector housingmay be constructed from suitable materials with reflective surfaces, such as aluminum or a similar materials. In some embodiments, the aluminum is polished or machined to reduce a surface roughness of the aluminum. The reflector housingmay be plated with nickel on all surfaces. The nickel layer provides corrosion protection and structural rigidity to the reflector housing. The nickel layer has a thickness of about 10 microns to about 40 microns, such as about 20 microns to about 30 microns. After the nickel is coated on the reflector housing, in some embodiments, the nickel in the inner surfaceis polished to remove surface scratches. The nickel is plated on the reflector housingby an electroless or electrolytic process.

As the reflectivity of the surface of reflector housingis increased, more energy is reflected from the lamps and towards a substrate in the processing chamber. To increase the reflectivity, the reflector housingis coated with a reflective coating. The reflective coating may be gold, silver, nickel, aluminum or a similar material. The reflective coating prevents the reflector housingfrom oxidizing and maintains a high level of reflectivity for the reflector housing. In various embodiments, the reflective coating is applied to the reflector housing via an electroplating process. The nickel layer described above is an under layer to the reflective coating. In embodiments having a gold reflective coating, the nickel layer provides beneficial properties to the reflective coating. In some embodiments, the inner surfaceof the reflector housingis additionally coated with a silicon oxide or ultraviolet (UV) enhanced coating. These coatings increase the damage resistance of the reflective coatings containing silver or aluminum.

One potential technique for electroplating the reflector housingmay include coating the first surface, the second surface, the inner surface, and the outer surfaceof the reflector housingwith reflective material. However, due to the costs associated with coating surfaces of the reflector housingwith reflective materials (e.g., gold or silver), in various embodiments, only the inner surfaceof the reflector housingis coated with the reflective material. In such embodiments, the first surface, the second surface, and/or the outer surfaceare not coated with the reflective material due to these surfaces being non-functional for reflecting, reducing material costs while still maintaining proper function in the reflector housing.

In various embodiments, in order to coat the inner surfacewith the reflective material (while avoiding coating one or more other surfaces with the reflective material), the other surfaces of the reflector housingmay be masked. However, current masking techniques may not be beneficial due to throughput concerns and cost. For example, one masking technique includes taping the other surfaces of the reflector housingor using liquid masking material commercially available for such purposes. Taping or using liquid masking has the downsides of each reflector housingneeding to be individually taped or masked (throughput concerns) and needing to tape or mask each uncoated surface (cost). To avoid these concerns, devices for masking need to be reusable and be able to electroplate multiple reflector housings(e.g. components) at once. The disclosure provides for masking fixtures (e.g. electroplating devices) allowing for masking of several reflector housings at the same time. As described in further detail below, the masking fixtures allow for high throughput and cost-effective masking of the reflector housings. By not coating the other surfaces, the masking fixtures greatly reduces the amount of coating material (e.g. gold or silver) used in the electroplating process reducing the cost.

is an isometric cross-sectional view of a masking fixture(e.g. electroplating device). The masking fixturecontains a first fixture surfaceand a second fixture surface. The second fixture surfaceis opposite the first fixture surface. Sidewallsconnect the first fixture surfaceto the second fixture surface. A plurality of holesextend from the first fixture surfaceto the second fixture surface. The holesextend through an internal volumedefined by the first fixture surface, the second fixture surface, and the sidewalls. The holesare configured to hold the reflector housings. A cathode connectorextends out of the sidewallto connect to a power supply (e.g., a rectifier). The cathode connectorconnects to each hole. An air bladderis disposed in the internal volume. The air bladdersurrounds each of the holes. The air bladderis fluidly connected to an air bladder inlet. The air bladder inletextends from the internal volumethrough the sidewall. The air bladder is configured to be filled with a gas (e.g., compressed air).

The materials of parts of the masking fixturevary. The first fixture surface, the second fixture surface, and the sidewallsmay include an insulator material such as plastics, elastomers, and ceramics. Plastics in the fluorocarbon family may be chosen due to cost and ease of manufacturing concerns. These plastics include Polytetrafluoroethylene (PTFE), Polyvinylidene fluoride (PVDF), Ethylene Tetrafluoroethylene (ETFE), ethylene-chlorotrifluoroethylene (ECTFE), Polychlorotrifluoroethylene (PCTFE), fluorinated ethylene propylene (FEP), and perfluoroalkoxy (PFA). Other plastics that may be used include Polyetherketoneketone (PEKK), polyaryletherketone (PAEK), Polyether ether ketone (PEEK), polyethylene terephthalate (PET), and Polypropylene (PP) or similar materials. Whereas, the cathode connectormay include a metal or metal alloy, such as titanium or copper. The cathode connectoris configured to provide electrons to the reflector housingwhen the reflector housingis electroplated and the material is selected to enhance electron transfer. In the internal volume, the air bladdermay include a molded elastomer or rubber. The air bladderis configured to expand against the holes, securing the reflector housingin the masking fixture. The air bladder inletexpands the air bladderby filling the air bladderwith a gas, such as compressed air.

is a cross-sectional view of the masking fixturewith the reflector housingpositioned in the hole. The reflector housingis electrically connected to the cathode connectorby a cathode insert. The cathode insertsupplies the reflector housingwith electrons that allow the reflector housingto be electroplated. The cathode connectoris connected to the power supply to supply electrons to the cathode insert. The cathode insertincludes a metal or metal alloy, such as titanium or copper. The reflector housingsare inserted into the holes. The air bladderis filled with air to secure the reflector housingsin the masking fixture. The air bladderseals the outer surface. The cathode insertseals the second surface. The first surfaceis sealed by a plurality of cover ringsdisposed in the plurality of holeson the first surfaceof the reflector housings.

An anode (not shown) may be inserted into an electrolyte solution with the masking fixture. The anode is an inert counter electrode to the cathode. The anode closes an electrical circuit in the electroplating process. The anode includes metals and metal alloys, such as titanium. The anode may be the anode described in. In some embodiments, the anode is an external anode (e.g. a side wall of a bath used to hold an electrolyte solution for the electroplating process). During the electroplating process, the reflector housingis secured in the masking fixture. The first surface, the second surface, and the outer surface are sealed off to prevent electroplating on these surfaces. The masking fixtureis disposed in the electrolyte solution. The electrolyte solution contains cations with the electroplating material. In some embodiments, the electroplating material is gold. When the electroplating material is gold, the electrolyte solution is selected to allow the gold electroplated layer to have the correct properties. The purity contributes to the reflectivity of the electroplated layer. The hardness contributes to the resistance to scratching of the electroplated layer. If the electroplated layer is intended to have different properties, then an electrolyte solution that provides a material other than gold may be selected to achieve those properties. The electrolyte solution includes ions of the material of the electroplate layer (e.g., gold ions). These ions are supplied to the electrolyte solution by dissolving salts into the electrolyte solution (e.g., gold salts).

As described above, the cathode connectoris connected to the power supply. The anode is also connected to the power supply. The power supply moves electrons from the anode to the cathode connector. From the cathode connector, the electrons are supplied to the reflector housing. The exposed surface of the reflector housing(inner surface) with the additional electrons interacts with the electrolyte solution. The cations in the electrolyte solution are reduced by the electrons, forming a material layer e.g. electroplating the inner surface. In some embodiments, the inner surfaceis electroplated with gold.

In some embodiments, the masking fixtureis used to electroplate other components besides the reflector housings. The other components may include brass or aluminum. When the other components are used, the other components include the nickel under layer and the reflective coating as described above for the reflector housing. The reflective coating includes the materials described above for the reflector housing. The other components may vary size. To fit the other components into the holes, the holesof the masking fixtureare modified. Some components may be large enough for the masking fixtureto have only one holeto cover the outer surface of one component. In some embodiments, the non-functional surfaces vary.

is an isometric view of a masking fixture(e.g. electroplating device). The masking fixtureis similar to the masking fixtureshown in. The masking fixturecontains a first fixture surfaceand a second fixture surface. The second fixture surfaceis opposite the first fixture surface. Sidewallsconnect the first fixture surfaceto the second fixture surface. A plurality of holesextend from the first fixture surfaceto the second fixture surface. The holesextend through an internal volumedefined by the first fixture surface, the second fixture surface, and the sidewalls. The holesare configured to hold the reflector housings. The first fixture surface, the second fixture surface, and the sidewallsmay include an insulator material such as plastics, elastomers, and ceramics. Plastics in the fluorocarbon family may be chosen due to cost and ease of manufacturing concerns. These plastics include Polytetrafluoroethylene (PTFE), Polyvinylidene fluoride (PVDF), Ethylene Tetrafluoroethylene (ETFE), ethylene-chlorotrifluoroethylene (ECTFE), Polychlorotrifluoroethylene (PCTFE), fluorinated ethylene propylene (FEP), and perfluoroalkoxy (PFA). Other plastics that could be used include Polyetherketoneketone (PEKK), polyaryletherketone (PAEK), Polyether ether ketone (PEEK), polyethylene terephthalate (PET), and Polypropylene (PP) or similar materials. The holesare defined by the internal volume. A sidewall of each holeis formed from the non-reactive material of the internal volume. The non-reactive material may include polytetrafluoroethylene or a similar material. A cathode connector (not shown) extends out of the sidewallto connect to a power supply. In some embodiments, the cathode connector is the cathode connectorshown in. In other embodiments, a different cathode connector is used. The cathode connector connects to each hole.

During electroplating, an anodewill be inserted into an electrolyte solution with the masking fixture. The anodeconnects to a power supply. As described in, the anodeincludes metals and metal alloys, such as titanium. The anodeis secured to the masking fixtureand branches out. The anodeextends into each holeof the masking fixture. In some embodiments, a different anode is used with the masking fixture. For example, the anode may be an external anode (e.g., a side wall of a bath used to hold an electrolyte solution for the electroplating process).

is a cross-sectional view of the masking fixturewith the reflector housingpositioned inside. The masking fixturefurther includes a plurality of cathode insertsand a plurality of O-ringsdisposed in each hole. The O-rings include a fluorocarbon elastomer or a similar material. Fluorocarbon elastomers may include Fluorine Kautschuk Material (FKM) and perfluoroelastomer (FFKM). Each reflector housingis electrically connected to the cathode connectorby a cathode insert. The cathode insertsupplies the reflector housingwith electrons that allow the reflector housingto be electroplated. The cathode connector is connected to the power supply to supply electrons to the cathode insert. The cathode insertsare positioned in the holesabove the second fixture surface. The reflector housingsare inserted into the holes. An O-ring of the plurality of O-ringssecures the reflector housingin the masking fixture. The O-ringsare positioned substantially level with the first fixture surfacein each hole. The non-reactive material of the internal volume seals the outer surface. The cathode insertseals the first surface. The second surfaceis sealed by the O-ring. The O-ringsblock the electrolyte solution from contacting the outer surfaceof the plurality of reflector housings.

In some embodiments, the masking fixtureis used to electroplate other components besides the reflector housings. These other components may include brass or aluminum. The other components may include a nickel underlayer and the reflective coating as described above for the reflector housing. The reflective coating includes the materials described above for the reflector housing. The other components may vary size. To fit the other components into the holes, the holesof the masking fixtureare modified. Some components may be large enough for the masking fixtureto have only one holeto cover the outer surface of one component. In some embodiments, the non-functional surfaces vary.

is a flow diagram of a methodfor electroplating the reflector housingusing a masking fixture. In various embodiments, the masking fixture may be the masking fixtureor the masking fixture. Unless specified, the methodis described in conjunction with masking fixturefor illustration purposes.

At operation, a plurality of the reflector housingsare positioned in the masking fixture. An example of a reflector housingis described in conjunction with. Each holeis filled with the masking fixture.

At operation, the plurality of the reflector housingsare sealed in the masking fixture. In various embodiments, the masking fixturecan seal the first surface, the second surface, and the outer surface. In embodiments that implement the masking fixture, the reflector housingis sealed by inflating the air bladder. The air bladdercovers the entire outer surface, preventing the metal containing electrolyte solution from contacting the outer surface. The first surfaceis covered by the cover ring. The second surfaceis covered by the cathode insert.

In embodiments that implement the masking fixture, the reflector housingis sealed by the O-ring. The O-ringprevents the metal containing electrolyte solution from contacting the outer surface. The outer surfaceis covered by the non-reactive material of the internal volume. The first surfaceis covered by the cathode insert. The cathode insertseals the first surface. The second surfaceis covered by the O-ring. The O-ringseals the second surface.

At operation, the masking fixtureis submerged in the electrolyte solution. In various embodiments, the outer surface, first surface, and second surfacedo not contact the electrolyte solution. While the outer surface, first surface, and second surfaceare not contacted, the electrolyte solution covers the inner surfaceof the reflector housing. The electrolyte solution contacts the inner surfaceby filling the holesof the masking fixture.

At operation, the electrolyte solution is electrically charged. The cathode connectorand the anode are connected to opposite sides of the power supply. The power supply transfers electrons from the anode to the cathode connector. The cathode connectortransports the electrons to the reflector housing, charging the inner surface.

At operation, the inner surfaceof the reflector housingis electroplated. The extra electrons in the reflector housingattract cations from the electrolyte solution. The cations attach to the exposed inner surface. The cations then combine with the electrons, forming an electroplate layer (e.g., a reflective coating) on the inner surface. The cations in the electrolyte solution are replaced by adding metal salts (e.g., gold salts when forming the gold electroplate layer) to the electrolyte solution. In some embodiments, the electroplate layer is gold. In other embodiments, the electroplate layer is nickel, silver, or a similar material. The electroplate layer has a thickness of about 50 micro inches to about 500 micro inches, such as about 100 micro inches to 300 micro inches. Once the selected thickness of the electroplate layer is achieved, the cathode connectorand the anode are disconnected from the power supply, and the masking fixtureis removed from the electrolyte solution. Finally, the reflector housingis removed from the masking fixturewith the inner surfaceelectroplated. In some embodiments, the inner surfaceof the reflector housingis additionally coated with a silicon oxide or UV enhanced coating. These coatings increase the damage resistance of the reflective coatings when the reflective coatings are silver or aluminum.

In summation, embodiments of the present disclosure generally relate to an apparatus used in semiconductor processing. More specifically, embodiments disclosed herein relate to electroplating apparatuses used in semiconductor processing chamber, such as reflector housings that are electroplated with a reflective material such as gold. While, conventionally, all surfaces of the reflective housings are coated, in various embodiments, only the inner surface may need to be coated. The reflective materials (e.g. gold) are expensive, so coating only the inner surface is beneficial. The outer surface, top surface, and bottom surface are covered by the masking fixture to prevent electroplating saving on cost of reflective material. The masking fixtures have the benefit of high throughput being a cost-effective masking technique. For example, the masking fixtures provided allow for masking of several reflector housings at the same time increasing the throughput. With regards to the cost, the masking fixture greatly reduces the amount of gold (or other reflective material) used in the electroplating process reducing the cost.

While the foregoing is directed to embodiments of the present disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.