Patent Application
20200194234
The disclosure relates to an apparatus for forming semiconductor devices on a semiconductor wafer. More specifically, maintaining systems for forming semiconductor devices.
In forming semiconductor devices, semiconductor device systems may use hazardous gases. Such systems are purged before the systems are opened.
To achieve the foregoing and in accordance with the purpose of the present disclosure, an apparatus for processing substrates is provided. A chamber comprises a chamber top and a chamber bottom, wherein the chamber bottom is detachably connected to the chamber top. At least one substrate support supports at least one substrate in the chamber. A substrate port allows a substrate to move into or out of the chamber. A seal creates a vacuum seal when the chamber top is on the chamber bottom. A manipulation system for manipulating an interior of the chamber when the chamber top is spaced apart from the chamber bottom comprises a sealing wall for creating a seal between the chamber top and chamber bottom when the chamber top is spaced apart from the chamber bottom and a manipulation port in the sealing wall, wherein the manipulation port allows a mechanical force to be provided through the sealing wall inside the chamber.
In another manifestation, a vacuum chamber opening system for a chamber is provided, wherein the chamber comprises a chamber top and a chamber bottom, wherein the vacuum chamber opening system seals the chamber as the chamber top is moved to be spaced apart from the chamber bottom. The vacuum opening system comprises a sealing wall for creating a seal between the chamber top and chamber bottom as the chamber top is moved to be spaced apart from the chamber bottom and a manipulation port in the sealing wall, wherein the manipulation port allows mechanical force to be provided through the sealing wall inside the chamber, when the chamber top is spaced apart from the chamber bottom.
These and other features of the present disclosure will be described in more details below in the detailed description and in conjunction with the following figures.
The present disclosure is illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings and in which like reference numerals refer to similar elements and in which:
The present disclosure will now be described in detail with reference to a few exemplary embodiments thereof as illustrated in the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present disclosure. It will be apparent, however, to one skilled in the art, that the present disclosure may be practiced without some or all of these specific details. In other instances, well-known process steps and/or structures have not been described in detail in order to not unnecessarily obscure the present disclosure.
In an exemplary embodiment,
A vacuum chamber opening system is connected between the chamber top 116 and the chamber bottom 120. The vacuum chamber opening system is designed to open the chamber for inspection without exposure to a hazardous environment. The vacuum chamber open system comprises a sealing wall 148 connected to a top mounting system 152 for mounting the sealing wall 148 to the chamber top 116 and a bottom mounting system 156 for mounting the sealing wall 148 to the chamber bottom 120. A load lock chamber 160 is connected to the sealing wall 148. The load lock chamber 160 is a chamber between the interior of the chamber 112 and the atmosphere with gas-tight doors between the load lock chamber 160 and the interior of the chamber 112 and between the atmosphere and the load lock chamber 160. A pump may also be connected to the load lock chamber 160. The load lock chamber 160 allows an object to pass into or out of the chamber 112 through the gas-tight doors. The load lock chamber 160 may minimize gases that pass from the chamber 112 to atmosphere or from atmosphere to the chamber 112. During a transfer of an object, the gas-tight doors stop the flow of gas from the chamber 112 to the load lock chamber 160 and the flow of gas from the atmosphere to the load lock chamber 160, when an object is in the load lock chamber 160. The load lock chamber 160 may be pumped down to remove some of the gas in the load lock chamber 160. After the load lock chamber 160 is sufficiently pumped down, one of the gas-tight doors is opened to allow the object to be removed out of the load lock chamber 160. Gloves 164 are also mounted in the sealing wall 148.
In operation, the substrate 124 may pass into the chamber 112 through the substrate port 146. The gas source 140 may provide a process gas, such as an etch gas, into the chamber 112. The RF source 132 provides RF power to form the process gas into a plasma. The RF source 132 may also provide a bias to accelerate ions to the substrate 124. The plasma may be used to perform a process on the substrate. Such processes may be one or more of etching, stripping, or depositing. After the substrate 124 is processed, the substrate 124 may be removed from the chamber 112 through the substrate port 146. After one or more substrates 124 have been processed, the chamber 112 may be opened to inspect the chamber 112, clean the chamber 112, service internal chamber parts, replace internal chamber parts, or test the chamber 112.
Without the vacuum chamber opening system, the chamber 112 may need to be decontaminated before opening the chamber 112. The processing of the substrate 124 frequently requires the use of hazardous chemicals. As a result, chamber parts become contaminated. A general procedure for chamber decontamination requires long pumping and purging (P/P) of the chamber 112 with inert gases (typically nitrogen or argon). In some cases, more than 6 hours are required for venting the chamber 112 to atmosphere prior to a safe open of the chamber 112. It is common to introduce water vapor inside the vacuum chamber during the P/P cycles. This is to enhance chamber decontamination by enabling chemical reaction between chemical residues and water. Resulting byproducts are frequently volatile and could be pumped away. However, in some cases, byproducts are not volatile and could not be safely removed. One example is low volatile fluorocarbon byproducts. Liquid HF (hydrofluoric) acid is a common reaction product that may accumulate on chamber parts. Besides being a health hazard, HF causes significant damage to internal chamber parts (especially ceramic and metal parts). Therefore, without the vacuuming opening system, long purge times are required before a chamber 112 can be opened for examination. The long purge times may increase damage to the internal chamber parts.
In order to improve vacuum chamber internal part design, engineers are required to have frequent access to chamber parts. This is required to study polymer accumulation and composition during silicon (Si) wafer etch processing. In addition, contaminated chamber parts inspection is required to optimize automatic chamber cleaning sequences. However, the current vacuum chamber open procedure does not allow safe access to any internal chamber parts. Moreover, after complete decontamination cycles, reactive polymer resides undergo a chemical reaction with water vapor (introduced during the P/P cycles). As a result, it is not possible to have an accurate analysis of polymer build up. The vacuum chamber opening system allows inspection of polymer accumulation without purging so that the polymer accumulation is not altered during the purging.
In this embodiment, the sealing wall 148 is a single layer of a flexible material, such as clear plastic. The sealing wall 148 must be resistant to damage from chemicals that the sealing wall 148 is exposed to. For example, preferably the sealing wall is of material that is not damaged by exposure to a halogen, such as hydrogen fluoride (HF) or hydrogen bromide (HBr) or sulfur oxides. In other embodiments, the sealing wall 148 may have two or more layers to provide additional sealing safety. In other embodiments, the sealing wall 148 may be more rigid and hinged, like bellows. The sealing wall 148 must be able to extend and between the chamber top 116 and the chamber bottom 120, as the chamber top 116 and the chamber bottom 120 are moved apart and then back together.
When the chamber needs to be opened, the pressure inside the chamber 112 is increased to be within 10% of the atmospheric pressure outside of the chamber 112. The pressure inside the chamber 112 being within 10% of the atmospheric pressure outside of the chamber 112 is defined as the difference between the atmospheric pressure outside the chamber 112 and the pressure inside the chamber 112 is no more than 10% of the atmospheric pressure outside the chamber 112. Preferably, the pressure inside the chamber 112 is increased to be within 1% of the atmospheric pressure outside the chamber 112. A small difference in pressure means that the sealing wall 148 and the top mounting system 152 and the bottom mounting system 156 need to be only strong enough to withstand and create a barrier for a small difference in pressure. In some embodiments, the pressure in the chamber 112 is greater than but within 1% of the pressure outside the chamber 112. An advantage in these embodiments is that the sealing wall 148 would bow outward. When the chamber top 116 is placed on the chamber bottom 120 the sealing wall 148 bowing outward would not be pinched between the chamber top 116 and the chamber bottom 120. Another advantage is that if there is a leak in the sealing wall 148, it would be easier to detect the leak. In other embodiments, the pressure in the chamber 112 is less than but within 1% of the pressure outside the chamber 112. An advantage in these embodiments is that if there was a leak in the sealing wall a net gas flow would be into the chamber 112 so that hazardous gas would not leak out of the chamber 112.
In various embodiments, the vacuum chamber opening system is detachably connected between the chamber top 116 and the chamber bottom 120. The vacuum chamber opening system may be attached to the chamber 112 only when the chamber 112 is to be opened for servicing. The vacuum chamber opening system may then be removed when not needed. In addition, a detachable vacuum chamber opening system would be easier to repair if any leaks are found. In other embodiments, the vacuum chamber opening system may be permanently connected to the chamber 112.
In other embodiments, the chamber 112 may be a deposition chamber or a stripping chamber or another substrate processing chamber. In various embodiments, the gas source 140 may be used to provide a gas to produce a set pressure. The gas source 140 may provide an inert gas such as nitrogen (N2) or argon (Ar) to maintain the set pressure. The pressure sensor 142 measures the pressure in the chamber 112. The exhaust pump 136 exhausts gas in the chamber in order to maintain the set pressure range. A feedback loop between the exhaust pump 136, gas source 140, and pressure sensor 142 may be used to provide a pressure system to detect a leak.
In some embodiments, robotic arm ports may replace or be provided in addition to gloves. Such robotic arm ports and gloves are manipulation ports that allow access for providing a manipulation force inside the chamber 112.
While this disclosure has been described in terms of several exemplary embodiments, there are alterations, modifications, permutations, and various substitute equivalents, which fall within the scope of this disclosure. It should also be noted that there are many alternative ways of implementing the methods and apparatuses of the present disclosure. It is therefore intended that the following appended claims be interpreted as including all such alterations, modifications, permutations, and various substitute equivalents as fall within the true spirit and scope of the present disclosure.
