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The disclosure of Kilby application '602 is best considered in connection with Fig. 6a thereof:
A thin wafer of single-crystal semiconductor material containing a diffused P-N junction shown there has been processed and shaped to form an integrated electronic circuit constituting a multivibrator. Among the elements of the circuit are resistors R1, R, and Rg and capacitors C, and C. Also formed are mesa transistors 5 T, and Tz. Although a semiconducting wafer that is “preferably silicon or germanium" is mentioned, P-type germanium is said to be used for the device shown. In producing the device, one side of the wafer is lapped and polished and then subjected to an antimony diffusion process to provide an N-type layer. Gold is evaporated through a mask to produce areas 51 to 54 which provide ohmic contact 6 with the N-type region such as the transistor base connections. Aluminum is evaporated through a mask shaped to provide the transistor emitter areas 56, which areas form rectifying contacts with the N-type layer. After utilizing a photosensitive resist process to etch the wafer to the proper shape, the photoresist is removed by a solvent and mesa areas 60 are masked by the same photographic process, and the wafer is again etched and the N-type layer removed in the exposed areas. Gold wires 70 are then thermally bonded to appropriate areas to make the necessary electrical connections. As examples, one wire 70 interconnects the emitter areas 56 of the two transistors T, and T, and base areas of the transistors are connected to contacts 51 and 52, respectively.
Kilby's Fig. 6a embodiment shows the gold connecting wires 70 insulated from the other circuit components and from each other by reason of their extending upwardly from the wafer into the air. How
5 The application includes an enlarged illustration of such a transistor revealing that its designation arises from its having a region of one type conductivity, as the base region, projecting like a plateau or mesa from the surface of a region of a different type conductivity, as the collector region.
& The record reveals that an ohmic contact is linear in contrast to the contact at a P-N junction which is nonlinear or rectifying.
ever, the application describes a modification in a partial paragraph thereof as follows: Instead of using the gold wires 70, in making electrical connections, connections may be provided in other ways. For example, an insulating and inert material such as silicon oxide may be evaporated onto the semiconductor circuit wafer through a mask either to cover the wafer completely except at the points where electrical contact is to be made thereto, or to cover only selected portions joining the points to be electrically connected. Electrically conducting material such as gold may then be laid down on the insulating material to make the necessary electrical circuit connections.
The issue which we must determine is whether Kilby '602 supports recitations such as those in count 1, supra, which require a conductor that is adherent to the surface of an insulating layer of oxide of the semiconductor and provides an electrical connection passing across a junction at the surface of the semiconductor between P-type and N-type regions.
Kilby's continuation-in-part application directly involved in the interference, filed after the Noyce patent issued, contains much material not included in the parent 602 application and its support for the counts in issue is unquestioned. Thus, the later application adds to the statement in ’602 that electrically conducting material such as gold may be "laid down” on the insulating material, a disclosure of "gold ribbons *** plated onto and adhering to the silicon oxide layer.” The involved application also adds a disclosure of a method for applying gold interconnections and includes several new figures which, taken with their description, clearly disclose the structure of the counts.
The board found the reference to an insulating material “such as silicon oxide" in the described modification of Fig. 6a supports the requirement for an insulating material consisting of "oxide of said semiconductor," because of the disclosure that either silicon or germanium could be used as semiconductor material, which precedes the statement that the wafer of Fig. 6a is of germanium. Apparently Noyce does not challenge that conclusion here.
With respect to the requirement of count 1 for a conductor adherent to the layer of insulation, the board referred to testimony taken by Noyce "to show that gold film deposited on silicon oxide is not adherent thereto." ? It stated that it was not particularly impressed by that testimony because it was directed exclusively to gold and took the view that the statement in Kilby '602 that electrically conducting
* It appears that the testimony for Noyce might be more precisely described as directed to showing that gold could not be deposited on silicon dioxide so as to adhere satisfactorily thereto at the time the Kilby '602 application was filled in 1959. Kilby joined issue on that matter and both parties conducted inter partes tests. Since we do pot rest our decision here on those tests, they will not be further discussed.
material “such as gold” may be laid down merely gives gold as an example. The board then concluded that "one skilled in the art of fabricating such devices *** would have no difficulty in selecting a metal which would unquestionably adhere to the silicon oxide layer.” It further referred to the fact that Kilby '602 discloses forming a capacitor on a semiconductor wafer by applying a coating of aluminum on a layer of silicon oxide previously provided on the wafer and stated that there was no suggestion by Noyce that aluminum or some other material known to be adherent would not be satisfactory to obtain a "conductive film."
The board also specifically considered the limitation in count 1 reading: * * * said conductor extending from said one contact over said [insulating) layer across said different portion of the junction It viewed that limitation as requiring only one insulating layer and one conducting film thereon crossing a junction between the P-type and N-type regions and stated that it would be satisfied if the single conductor 70 interconnecting the emitter contacts 56 of Fig. 6a of Kilby were “provided by a conductive film on a layer of silicon oxide.” While conceding that Kilby '602 does not expressly point out, or distinctly show, where the junction between P-type and N-type regions is found or where there is a “different portion" of that junction which is crossed by the insulating layer and overlaying conductor, the board held that those features are necessarily implicit therein."
Before us, Noyce stresses the argument that a "conductor adherent to the surface of the oxide and crossing a junction” is an essential feature of the invention and is not disclosed by the Kilby '602 application. He observes that Kilby must rely for the conductor adherent" limitation of count 1 on the sentence in the reference to the modification of his Fig. 6a structure which states that “[e]lectrically conducting material such as gold may then be laid down on the insulating material to make the necessary electrical circuit connections." It is Noyce's position that this suggestion that the electrical connection be “laid down" on the insulating layer does not teach that it be "adherent” thereto and that such adherency is not otherwise taught in the '602 application.
Kilby does not deny that his ’602 application lacks language stating that a conductor in his modified Fig. 6a construction is "adherent” to the insulating layer. He nevertheless contends that the application should be interpreted as supporting the limitations in question.
As pointed out by Noyce, the present case generally parallels the case of Dyer v. Field, 55 CCPA 771, 386 F. 2d 466, 156 USPQ 85 (1967). There, the junior party Field was involved in interference
on a continuation-in-part application which was expanded substantially over the parent application relied on for priority with respect to the very feature of the invention in issue that was in controversy. The same is true here with the additional aspect that Kilby's directly involved application was filed after Noyce's patent issued. However, we agree with Kilby that Field's being involved in the interference on a new application having an expanded disclosure “alone was not what caused the final ruling adverse to Field.” Rather, the decision there was based on a finding that the earlier Field application did not disclose the invention in issue. So too, the determinative matter here is whether earlier filed Kilby '602 supports the counts.  The criterion for determining whether an application supports a count is whether the "necessary and only reasonable construction” to be given the disclosure by one skilled in the art is one which provides such support. Binstead v. Littmann, 44 CCPA 839, 242 F. 2d 766, 113 USPQ 279 (1957). That requirement is the same where one relies on the earlier application for support in order to obtain the benefit of its filing date as where support in an application directly involved in interference is in issue. See Guyer v. Cramer, 50 CCPA 1386, 318 F. 2d 757, 138 USPQ 125 (1963). The burden on one copying a claim from a patent was recently summarized in Gubelmann v. Gang, 56 CCPA 1013, 408 F.2d 758, 161 USPQ 216 (1969), as follows: One copying a claim from a patent has the burden of showing that his applica. tion clearly supports the count. In determining applicant's right to make a copied claim, all limitations in the claim will be considered material and doubts arising as to such right must be resolved against the copier. Where support must be based on an inherent disclosure, it is not sufficient that a person following the disclosure might obtain the result set forth in the count; it must invariably happen. See Smith v. Wehn, 50 CCPA 1544, 318 F. 2d 325, 138 USPQ 52, and Dreyfus and Harrison v. Sternau, 53 CCPA 1050, 357 F. 2d 411, 149 USPQ 63.
Although the board held here, as already noted, that one skilled in the art would have no difficulty in "selecting" a metal which would adhere to the silicon oxide layer suggested in the Kilby ’602 application, that finding avoids the real issue which is whether the application includes a disclosure that the conductor is to be adherent to the layer. The board did subsequently get to that issue, stating:
Noyce urges that there is nothing in the paragraph relied on in the parent Kilby case to indicate that Kilby had any concern about whether the conducting material would have any adherence at all since there is only the statement that the conducting material be "laid down on the insulation material". This is true only to the extent that Kilby clearly suggested no particular degree of adherence as mentioned above. We think that the clear import of the Kilby disclosure is that the device constructed in the manner taught would be usable under ordinary circumstances and would be expected to withstand normal handling. In our opinion this would necessarily involve at least some degree of adherence * * *. [Emphasis supplied.)
No sound support is seen for the board's view that "at least some degree of adherence” would necessarily be involved. As pointed out by Noyce, the implication of the reasoning by which the board reaches that conclusion is that “Kilby's own preferred embodiment in ’602, shown in Fig. 6a, where the gold wires 70 clearly were not adherent, was not'usable under ordinary circumstances.'”
The disclosure relied on by the board of a coating of aluminum on silicon oxide in a capacitor is illustrated in Fig. 2a of Kilby '602, reproduced below:
There, a body 15a of semiconductor material constitutes one plate of the capacitor. Silicon oxide is applied to that body by evaporation or thermal oxidation techniques to serve as the dielectric 18 of the capacitor. The second plate 19 is provided by evaporating on the oxide dielectric a conductive material, gold or aluminum being described as satisfactory.
While that disclosure indicates that it was known in 1959 that aluminum could be deposited on an oxide layer to form the plate of a capacitor, it does not seem to us to constitute any clear suggestion that conductors interconnecting terminals of semiconductor devices should be so deposited.
The gist of the reasoning of Kilby on the point under consideration is found in the following argument in his brief:
The word "laid" (the past participle of the word “lay") has quite a large number of meanings. In addition to laying down as a carpet on a floor, there are other meanings given in Webster's International Dictionary, such as to dispose of as over a surface; as to lay a pavement; to coat. For the word "laying" the meaning is given as that of “the act of one who acts or sets, puts, places, fires, etc." The intention of Kilby was to describe in a very broad sense the act of making appropriate and necessary electrical connections to semiconductor devices wherein an inert and insulating material such as silicon oxide separated the electrical conductor from the semiconductor substrate. It was Kilby's purpose to describe an operative embodiment so as to teach the art the means of making necessary electrical connections in integrated circuits. The words "laid down" quite obviously mean depositing or plating by an appropriate means such