In patent prosecution, sometimes the arguments that successfully move an application to allowance are highly technical in nature. That is why having patent professionals with technical expertise involved in the drafting and prosecution of an application is so important. While technical expertise is a necessary component of successful patent prosecution, it is not sufficient. Patent professionals also need to be able to recognize layman issues that can be just as dispositive in the end.
One of Applied Materials applications illustrates this aspect. And while the issue is easy to spot with 20/20 hindsight, the challenge for patent professionals is to spot such issues early in the drafting process
Application 15/691,157 relates generally to power delivery for plasma processing in semiconductor process chambers. Claim 1 sets forth one of the independent claims:
1. A system for generation and delivery of a pulsed, high voltage signal for a process chamber, comprising:
a high voltage supply, disposed remotely from the process chamber, to generate a high voltage signal;
a pulser, comprising a separate component from the high voltage supply, disposed relatively closer to the process chamber than the high voltage supply to pulse the generated high voltage signal;
a first shielded cable to deliver the high voltage signal from the remotely disposed high voltage supply to the pulser to be pulsed; and
a second shielded cable to deliver a pulsed, high voltage signal from the pulser to the process chamber.
One of the key advantages of the claimed system is the remote location of the high voltage supply relative to the process chamber. As well understood by those skilled in the fab arts, process chambers are typically located in clean rooms where real estate is at a premium. Whenever it is possible to move some aspects of the equipment to another location, such as a subfab, this can save space and thus costs. Applied Materials specifically recognized this advantage in their application.
The problem comes as to the term “remote” in that the examiner applied prior art that showed the high voltage supply clearly in the clean room, but mounted in the immediate vicinity of the cathodes on an associated electro-vacuum passage on the outside of the processing chamber wall. According to the examiner, because it was located on the outside of the processing wall, it was remote from the processing chamber and met the claim limitations.
Applied Materials tried explaining that remote would be understood, in light of the specification (which points out the real estate issue in a clean room), to mean that the high voltage supply must be in a different location and not just outside of the process chamber.
Unfortunately, the specification was limited to the term “remote” and the specific example of a room below the clean room where large pumps, compressors and power sources that don't have to be in the clean room environment are located. In hindsight, given the importance of the “remote” aspect to the invention in terms of solving a problem with the current state of the art, more details and different levels of abstraction around the “remote” concept may have been prudent in enabling an amendment (or backup amendments in dependent claims) so as to distinguish the cited art while still not overly narrowing the claim scope.
As the PTAB explained, the problem for the applicant was that:
We have read the portions of the Specification Appellant relies upon to define the term “remote” and find no description that distinguishes the claimed invention from Cremer’s method. In fact, paragraph 24 of the Specification describes “the high voltage DC power supply 202 is illustratively located in a subfab 210, a room below the clean room [that contains the processing chamber].” See Application Figure 2. At best, this portion of the Specification describes the high voltage power supply as located apart from, yet in the vicinity of (“room below”), the processing chamber. Further, Appellant refers to this disclosure as an embodiment of the invention and the specific distinguishing details of this embodiment are not present in the claims. Reply Br. 5. Thus, Appellant fails to explain adequately why this description distinguishes the claimed invention from Cremer’s placement of component 6 in the immediate vicinity outside of the processing chamber wall, as interpreted by the Examiner.
It is important to not only understand the technical advantages and improvements offered by an invention, but also to consider how claim terms may be interpreted (overly) broadly by the USPTO. Extra description at various levels of abstraction can create amendment opportunities that can help when unexpected interpretations and/or prior art are applied by the examiner.