In patent applications reciting a controller configured to carry out certain processing steps, there is substantial variation on whether, and to what extent, the claimed processing steps should be given patentable weight by US examiners during prosecution. See our previous post here.
There are different ways in which examiners can try to avoid having to find prior art to apply to the claimed processing steps in the above claim structure. A first out is for the examiner to assert that the prior art structure is capable of performing the same function recited in the claim. Here, the examiner may cited to MPEP 2114 and assert that a claimed structure must distinguish the prior art by more than mere function. An applicant may counter this argument by claiming a special purpose computer that is specifically structured via programming to perform the claimed operations. Sometimes reciting memory with instructions can aid this argument, enabling the applicant ton convince the examiner that the the prior art controller is not capable of performing the claimed operation. In other words, the applicant can argue that while it might be possible to install software that would allow the prior art’s controller to perform the claimed operation, the prior art structure as disclosed is not capable of doing so on its own.
However, a second approach an examiner might consider is to focus on intended use. As explained in the MPEP, a claim containing a recitation of the manner in which an apparatus is intended to be employed does not differentiate the claimed apparatus from prior art if the prior art has the same structure (e.g., a generic controller).
That is the approach an examiner took recently in an Applied Materials invention (Appeal 2023-002042, Application 17/037,165). Claim 1 on approach is reproduced below:
1. A processing system, comprising:
a first processing chamber; and
a controller configured to cause a process to be performed in the processing system, the process comprising:
removing carbon containing contaminants from a native oxide layer on a surface of a substrate by performing a reducing process using a hydrogen containing plasma in the first processing chamber; and
after removing carbon containing contaminants, removing the native oxide layer from the substrate by performing an etch process using a fluorine containing plasma in the first processing chamber.
The only support in the specification for the structure of the controller allegedly was that “the chamber 500 includes a controller 502 for controlling processes within the chamber.” Thus, the generic controller was not even specific enough to specify software stored in memory, or some other special purpose programming that could constitute structure.
The primary rejection relied on prior art that admittedly did not disclose several aspects of claim 1, namely that the cited prior art did not disclose “removing carbon containing contaminants from a native oxide layer on a surface of a substrate and after removing carbon containing contaminants, removing the native oxide.” Nevertheless the examiner relied on the doctrine of “intended use” to ignore such features.
The PTAB essentially agreed - doing so by rearranging the claim terminology in a way that suited its finding as follows (internal citations omitted):
Claim 1 recites a system including a processor configured to cause a process that includes 1) performing a reducing process using a hydrogen containing plasma so as to remove carbon containing contaminants, and 2) performing an etch process using a fluorine containing plasma so as to removing the native oxide layer from the substrate in the first processing chamber. In this claim, “removing carbon containing contaminants” is a statement of intended purpose. The hydrogen containing plasma is used for the purpose of removing carbon containing contaminants. Similarly, “removing the native oxide layer from the substrate” is a statement of intended purpose. The fluorine containing plasma is used for the purpose of removing the native oxide layer from the substrate. Accordingly, applying the broadest reasonable interpretation, such terms are not limiting and may not be relied upon to distinguish over the prior art.
Note that there were method claims present in the application, but were restricted and thus not examined or part of the appeal. While the applicant elected with traverse, no follow up petition appears to have been filed. The applicant can consider a divisional application, but whether the alleged intended use elements will be given patentable weight if presented as a method is left to be determined. Noting how the PTAB rearranged the claim elements to find intended use indicates it may be an uphill battle for the applicant.
It is important to recognize the potential weak points in drafting broad generic controller elements limited only by alleged function. It may be helpful to have backup in the specification illustrating how unique structure is achieved with specialized instructions in a specific structure.