Method and associated structure for authenticating an integrated circuit with authentication film

Abstract

Method for authenticating an IC structure (100), wherein the method comprises: a formation of a first authentication film material (130) within the IC structure (100), wherein the composition of the first authentication film material (130) differs from an adjacent material within the IC structure (100), wherein the first authentication film material (130) is formed in a part of a wiring layer (102) of the IC structure (100) under a polyimide layer, wherein the part of the wiring layer (102) has at least one opening (150) through the polyimide layer dimensioned for the evaporation of the first authentication film material (130); a conversion of the first authentication film material (130) into a cavity (140) within the IC structure (100); and a generation of an authentication plan of the IC structure (100), wherein the authentication plan includes a location of the cavity (140) in the IC structure (100) for authentication of the IC structure (100).

Description

Technical field

[0001] Embodiments of the invention generally relate to the authentication of integrated circuits (ICs). More specifically, embodiments of the invention provide a structure and a method for authenticating ICs using authentication film (AF) materials. background

[0002] In the microelectronics industry, the possibility of reverse engineering chips has become an increasing problem. With the growing prevalence of reverse engineering, counterfeit chips have begun to enter the supply chain. In some cases, an external company that temporarily possesses a product in the supply chain may be able to introduce additional circuitry or "backdoors" into sensitive active parts of a product.

[0003] Counterfeiting and / or tampering can occur in many contexts. Using a medical device as an example, the effects of a counterfeit chip can range from harmless effects (e.g., incoherent data on a display) to critical failures (e.g., faulty timing of a pacemaker). In some cases, these effects are difficult to distinguish from random errors and / or age-related deterioration. As partnerships between manufacturers worldwide become increasingly important for production efficiency, potential vulnerabilities in the supply chain have become ever more critical for both manufacturers and customers.

[0004] US 2011 / 0248412A1 mentions a method for unique chip identification for organic laminate packaging by modifying a material on the wafer that includes a variety of chips, with each chip being given a unique identification mark.

[0005] US 2008 / 0 001 147 A1 describes the manufacture of a semiconductor device in which an insulating film is formed on the surface of a semiconductor substrate in the circuit area, while in the monitor area five insulating films are formed running parallel to each other, onto which gate insulating films and gate electrodes are then applied at the same distance.

[0006] US 2005 / 0 199 995 A1 mentions a semiconductor device encapsulated in a wafer-level chip-size package (WLCSP) and having multiple pad electrodes on the surface of a semiconductor chip.

[0007] JP H08-83861 A describes a metal foil material that is applied to the surface of a resin-sealed semiconductor package to achieve high reliability through improved moisture resistance, solder resistance, and heat resistance. Summary

[0008] According to the invention, a method according to claim 1 and a structure according to claim 8 are provided. Brief description of the drawings

[0009] These and other features of this invention are more easily understood from the following detailed description of the various aspects of the invention in conjunction with the accompanying drawings, which depict different embodiments of the invention, and in which: Fig. Figure 1 shows a cross-sectional view of an IC structure with an authentication film material (AF) according to embodiments of the invention. Fig. Figure 2 shows a top view of an IC structure with an initial structure made of AF material according to the embodiments of the invention. Fig. Figure 3 shows a cross-sectional view of the conversion of the AF material into a cavity according to embodiments of the invention. Fig. Figure 4 shows a top view of an IC structure with a structure of cavities according to the embodiments of the invention. Fig. Figure 5 shows a cross-sectional view of a formation of another AF material in parts of a cavity according to the embodiments of the invention. Fig. Figure 6 shows a top view of an IC structure with a structure made of AF material and cavities according to the embodiments of the invention. Fig. Figure 7 shows a cross-sectional view of AF material in a metal wiring layer according to embodiments of the invention. Fig. Figure 8 shows a cross-sectional view of the conversion of part of the AF material in the metal wiring layer into a cavity according to embodiments of the invention. Fig. Figure 9 shows an illustrative flowchart of methods for authenticating an IC structure according to embodiments of the invention.

[0010] It should be noted that the drawings of the invention are not necessarily to scale. The drawings are intended to illustrate only typical aspects of the invention. Within the drawings, the same numbering refers to identical elements. Detailed description

[0011] When an element such as a layer, area, or substrate is described as "on" or "above" another element, it may be located directly on top of the other element, or there may be intermediate elements. However, if an element is described as "directly on" or "directly above" another element, there can be no intermediate elements. When an element is described as "connected" or "coupled" to another element, it may be directly connected or coupled to the other element, or there may be intermediate elements. However, if an element is described as "directly connected" or "directly coupled" to another element, there are no intermediate elements.

[0012] References in the description to "an embodiment" or "an embodiment" of the present invention, as well as other variations thereof, mean that a particular feature, structure, property, etc., described in connection with the embodiment, is included in at least one embodiment of the present invention. Therefore, the expressions "in an embodiment" or "in an embodiment," as well as any other variations appearing at different points in the description, do not necessarily all refer to the same embodiment. It should be understood that the use of " / ", "and / or," and "at least one of," e.g., in the cases "A / B," "A and / or B," and "at least one of A and B," is intended to include only the selection of the first listed option (a), only the selection of the second listed option (B), or the selection of both options (A and B).Another example: In the cases "A, B and / or C" and "at least one of the options A, B and C", this wording should include only the first listed option (A), or only the selection of the second listed option (B), or only the selection of the third listed option (C), or the selection of the first and second listed options (A and B), or the selection of the first and third listed options (A and C), or the selection of the second and third listed options (B and C), or the selection of all three options (A, B and C). As is readily apparent to a person skilled in the art, this can be extended to include any number of listed options.

[0013] Embodiments of the invention relate to methods for authenticating structures for integrated circuits (ICs) and structures comprising authentication features. Methods according to the invention can include forming an authentication film material (e.g., one or more material layers that can be converted into cavities by vapor deposition, etching, and / or other techniques) within an IC structure. The authentication film material can be formed as one or more regions or structures. The authentication film material can be dimensioned such that portions of it can be selectively or non-selectively treated (e.g., removed). If authentication film material is present, a portion or all of it can be converted into a cavity. The cavity can be optically detectable and / or distinguishable from adjacent materials using a microscope, while the authentication film material itself can be optically indistinguishable.The procedure also includes generating an authentication plan of the IC structure, which specifies the location of the cavity and, optionally, all parts of the AF material remaining within the IC structure. The authentication plan can be provided exclusively to a recipient of the IC structure, for example, via one or more secure communication channels. The recipient can then examine the IC structure to verify that the empty and, if applicable, remaining parts of the AF material correspond to the relevant locations in the authentication plan. In some cases, each individual unit of the IC structure may have a unique authentication plan.

[0014] An IC structure according to the invention can comprise various physical elements for implementing methods according to the invention and / or other authentication features. An IC structure according to the invention can have one or more cavities located in an area horizontally offset from one or more electrically active elements, e.g., within a local interconnect or metal wiring layer. The location of the cavities can provide an authentication pattern for the IC structure. In further embodiments, portions of the AF material can also be located within the area of ​​the IC structure. Further processing and / or modification of the IC structure can result in remaining portions of the AF material being converted into cavities, indicating unauthorized processing and / or manipulation of the IC structure.

[0015] With reference to Fig. 1. Embodiments of the invention may include and / or be implemented on an integrated circuit (IC) structure 100. The methods described herein may yield an IC structure according to one or more embodiments of the invention. The IC structure 100 may represent a portion of a starting material distributed over a two-dimensional area in the XY plane, and Fig. Figure 1 shows a cross-section of the IC structure 100 in plane XZ. The IC structure 100 comprises a set of metallic wiring layers 102 with several different layers (e.g., a first metal layer 104 and a second metal layer 106), with various additional layers (not shown) arranged below. The metallic wiring layer(s) 102 can be arranged above one or more layers comprising various devices, e.g., transistors, resistors, capacitors, etc. The design and positioning of such components are generally known and not relevant to the embodiments of the present invention and are therefore omitted.

[0016] The metallic wiring layer(s) 102 described here may include several layers of insulating material and several metal wires in each layer. The various layers of the metallic wiring layer(s) 102 may include active circuits, such as metal wires 108, vias 110, and / or other elements like conductive intermediates and / or other conductive elements. The conductive materials of the metallic wiring layer(s) 102, such as the metal wires 108 and / or the vias 110, may include materials such as copper (Cu), aluminum (Al), and / or any other type of conductive material. The conductive materials of the metallic wiring layer(s) 102 may extend horizontally or vertically through a set of dielectric intermediate layers (ILDs) 112.The ILD layer(s) 112 can be formed from any currently known or subsequently developed substance for electrical insulation, e.g., silicon nitride (Si3N4), silicon oxide (SiO2), fluorinated SiO2 (FSG), hydrogenated silicon oxycarbide (SiCOH), porous SiCOH, boron phosphosilicate glass (BPSG), silsesquioxanes, carbon-doped oxides (i.e., organosilicates) containing silicon (Si), carbon (C), oxygen (O), and / or hydrogen (H) atoms, thermosetting polyarylene ethers, a silicon-carbon-containing polymer material for spin-molding, near-frictionless carbon (NFC), or layers thereof. The first layer 104 can be an uppermost metal layer of the metal wiring layer(s) 102, and the second layer 106 can be the next layer below it. The metallic wiring layer(s) 102 can have any number of layers, each containing its own set of metal wires 108, vias 110, etc.include.

[0017] The IC structure 100 can comprise a local interconnect layer (LI) 114 above the metal wiring layer(s) 102 for electrically coupling the metal wiring layer(s) 102 to other IC components. The LI layer 114 can comprise a polyimide material 116, e.g., one or more photosensitive polyimides (PSPIs), benzocyclobutene (BCB), epoxy, poly(p-phenylene-2,6-benzobisoxazole (PBO), and / or similar materials alone or in any conceivable combination. As mentioned elsewhere, one or more compounds within the polyimide material 116 can be porous or non-porous, and porous materials can allow evaporated materials to pass through the polyimide material 116 in processes according to the invention. The LI layer 114 can also itself comprise one or more LI conductors 118, e.g.,Contact surfaces and / or wires for connecting metal wires 108 and / or through-holes 110 of the metal wiring layer(s) 102 to various connection components (e.g., solder points and / or structures for connection to an IC). Various layers of insulating material can protect the LI conductors 118 of the LI layer 114 from the polyimide material 116, and such materials can include an oxide layer 120 formed on the LI conductor(s) 118 and a nitride layer 122 formed between the oxide layer 120 and the polyimide material 116. Depending on the type of IC and / or the intended application of the IC structure 100, the oxide layer 120 and / or the nitride layer 122 can be omitted and / or used in conjunction with additional insulating materials.

[0018] Embodiments of the invention may include the formation of a first authentication film (AF) material 130 within the IC structure 100. In one example, the first AF material 130 is formed above the metallic wiring layers 102 and within the LI layer 114, but as discussed in detail elsewhere herein, the first AF material 130 may optionally be formed within the metallic wiring layer(s) 102. The first AF material 130 may, for example, comprise any type of material that can be evaporated under prescribed conditions and may thus include one or more carbon-based energy removal film (ERF) materials. In such cases, the first AF material 130 may be evaporated by applying heat to a predetermined temperature that is lower than the phase change temperature of other materials in the IC structure 100.The first AF material 130 can in this case comprise one or more carbon-based organic materials (e.g., porogens) that are deposited by spin coating or chemical vapor deposition (CVD) and cured using ultraviolet light. Such materials can be cured at a temperature between approximately three hundred and four hundred degrees Celsius (°C). The first AF material 130 can, in various embodiments, form a C. x H y-The first AF material 130 comprises a carbon-based compound, where "x" and "y" represent different numbers of carbon and hydrogen atoms, respectively. In further examples, the first AF material 130 can comprise an oxide layer, a nitride layer, and / or another material that can be selectively removed from adjacent materials (e.g., ILD layer(s) 112, polyimide material 116, etc.). In this case, portions of the first AF material 130 can be removed by forming a mask (not shown) and etching the first AF material 130 through openings in the mask. In each embodiment, the first AF material 130 can be formed to a thickness of at least about fifty angstroms over the metallic wiring layer(s) 102, and in further embodiments, it can have a thickness of ten micrometers (µm) or more over the metallic wiring layer(s) 102.In each embodiment, the composition of the first AF material 130 cannot be optically distinguished from adjacent materials (e.g., ILD layer(s) 112, polyimide material 116) without the use of improved imaging technology (e.g., thermal imaging, improved microscopy, etc.).

[0019] With reference to Fig. 2. The first AF material 130 can be formed in a first region R1 of the IC structure 100, which is located away from one or more electrically active components or is otherwise separated from active components in a second region R2 of the IC structure 100. Such active components can include LI conductors 118 (e.g., wires, pads, etc., as discussed herein) and / or other conductive materials. As in Fig. As shown in Figure 2, several regions of the first AF material 130 can be formed in a pattern 132 on the IC structure 100. The pattern 132 can comprise four regions of the first AF material 130 to generate a group of different shapes in an exemplary implementation (e.g., circle, rhombus, hexagon, star, as shown). Although the first AF material 130 and the pattern 132 in Fig. While the first AF material 130 is represented within the polyimide material 116, in other implementations, as described herein, it can be located within the metal wiring layer(s) 102. Any conceivable number of areas of the first AF material 130 can be formed on the IC structure 100 to create symbols such as easily identifiable symbols, e.g., letters, shapes, icons, and / or areas of the first AF material 130 that appear to have no recognizable pattern or shape. However arranged, the pattern 132 of the first AF material 130 can be derived from a design for the IC structure 100. Further processing according to the invention can include converting the first AF material 130 into empty space (“cavities,” as described herein) that can be compared with an authentication plan to verify that the IC structure 100 has not been modified without authorization.

[0020] Fig. Figure 3 shows a cross-sectional view of a process for converting the first AF material 130 ( Fig. 1, Fig. 2) into cavities 140 for authentication of the IC structure 100. In some embodiments (e.g., when the first AF material 130 comprises an ERF material), the methods according to the invention may include exposing the IC structure 100 to ultraviolet light at elevated temperature (e.g., 300 to 400 °C) to vaporize all exposed parts of the first AF material 130. In further examples, e.g., when the first AF material 130 comprises an oxide, the first AF material 130 may be transformed into a cavity or cavities 140 by forming a mask on the IC structure 100 and etching the first AF material 130 from the IC structure 100. The conversion of the first AF material 130 into one or more cavities 140 cannot have any effect on the electrically active components in the second area R2 (e.g., due to the arrangement of the first AF material 130 in the first area R1, away from the electrically active components of the IC structure 100)Conductive traces within the LI layer 114 and / or metal wiring layers 102) are present. After cavities 140 have been formed, all heat sources, etching tools, etc., used for the conversion can be removed from the IC structure 100.

[0021] The conversion of the first AF material 130 into cavities 140 can lead to a pattern 142 of cavities 140 on the IC structure 100 (see Fig. 4) In comparison to the first AF material 130, the cavities 140 can be viewed in relation to adjacent materials (e.g. ILD layer(s) 112 ( Fig. 1, Fig. 2) polyimide material 116) by means of a microscope or other visual analysis of the IC structure 100. The pattern 142 can comprise the same symbols (e.g., shapes, letters, and / or other identifiable structures) with which the first AF material 130 was previously formed in the IC structure 100. The pattern 142 can be completely contained within the first region R1 of the IC structure without any active elements (e.g., LI conductors 118) therein, so that the cavities 140 do not interfere with the active components of the IC structure 100 in the second region R2. Methods according to the invention can include an optical analysis of the IC structure 100 (e.g., using a microscope) to locate the pattern(s) 142. If the pattern(s) 142 is / are in the same location as an authentication plan for the IC structure 100, the recipient of the IC structure 100 knows that the product is authentic.In some cases, the conversion of the first AF material 130 into one or more cavities 140 can be carried out by the receiver itself, so that the location of the pattern 142 is not known or visible to an intermediate receiver of the IC structure 100 who has not received the authentication plan for the IC structure 100.

[0022] With reference to Fig. 5. Some methods and / or structures according to the invention may only involve the partial removal and / or reshaping of AF material(s) to obtain a second AF material 144 on the IC structure 100. In this case, both the cavities 140 and the second AF material 144 can be used for authentication of the IC structure 100. Fig. Figure 5 shows a cross-section of the IC structure 100 with part of the cavity 140 filled with the second AF material 144. The second AF material 144 can be formed, for example, by creating an additional mask (not shown) and applying the second AF material 144 to the exposed area of ​​one or more cavities 140. In another example, the second AF material 144 can be formed by using only part of the first AF material 130 ( Fig. 1, Fig. 2) is converted into the cavity(s) 140, e.g. by controlled application of UV light, etching, etc., to obtain the second AF material 144 and the cavity(s) 140.

[0023] Fig. Figure 6 shows a top view of the IC structure 100, where the pattern 142 comprises a combination of cavities 140 and second AF material 144. In this case, some cavities 140 may be completely free of second AF material 144, some parts of the second AF material 144 may not contain any cavities 140, and / or different areas may contain different amounts of one or more cavities 140 and / or second AF material 144. The distribution of the second AF material 144 over the IC structure 100 may be uneven; that is, different amounts of the second AF material 144 may appear randomly or pseudorandomly distributed over the cross-sectional area of ​​the IC structure 100, or otherwise may not exhibit a recognizable pattern without the aid of an authentication plan.Optical inspection of the IC structure 100 using a microscope allows the user to identify the location of the cavities 140 in relation to the second AF material 144 and adjacent materials, in order to compare them with an authentication plan of the IC structure 100. The presence of the second AF material 144 can enable several authentication phases, for example, by identifying the pattern 142 containing the second AF material 144 before the second AF material 144 is transformed into additional cavities. The resulting pattern 142 without cavities 140 can then be authenticated using a further authentication plan. With this approach, multiple receivers of the IC structure 100 can authenticate the IC structure 100 based on the position of the cavities 140 and / or the second AF material 144.

[0024] With reference to Fig. 7. The methods according to the invention can include forming a first AF material 130 within the metal wiring layer(s) 102 before the LI layer 114 is formed over it. In one example, the first AF material 130 can be formed within portions of the first metal layer 104, but it is also possible for the first AF material 130 to be formed additionally or alternatively within the second metal layer 106 and / or any other layer of the metal wiring layer(s) 102 in the IC structure 100. In this case, the polyimide material 116 or another metal layer within the metal wiring layer 102 can cover an upper surface of the first AF material 130. Each of the different techniques for converting the first AF material 130 into cavities 140 discussed here can be applied to the AF material(s) 130 within the metal wiring layer(s) 102.If the first AF material (or materials) 130 comprises oxide materials, parts of the metal wiring layer(s) 102 can, for example, be removed by etching with a mask to create cavities 140 at the desired locations. The polyimide material(s) 116 and / or parts of the underlying metal wiring layer(s) 102 can also have openings 150 for the vaporization of the first AF material (or materials) 130 under the influence of heat. To allow vaporized AF material (or materials) to escape from the IC structure 100, the opening(s) 150 can have a diameter of, for example, at least approximately one micrometer (µm), although this can vary in further embodiments.

[0025] Fig. Figure 8 shows a cross-sectional view of a process for converting first AF material(s) 130 into one or more cavities 140 by evaporation. Here, UV light and / or heat from an external source can be applied to the IC structure 100 to control the temperature of the first AF material 130 ( Fig. 7) to increase to its evaporation temperature. The material composition of the first AF material 130 (e.g., carbon-based ERF materials) can be chosen such that it evaporates at temperatures too low to affect other parts of the IC structure 100, including the active materials in the second region R2. At the evaporation temperature, evaporated portions of the first AF material 130 can escape from the IC structure through the opening(s) 150, thereby transforming the first AF material 130 into a cavity or cavities 140. Non-evaporated portions of the first AF material 130 can remain within the metal wiring layer(s) 102 as the second AF material 144.In cases where the polyimide material 116 has a porous compound that is permeable to evaporated parts of the first AF material 130, the opening(s) 150 can be omitted, and the cavity(ies) 140 can be formed by the passage of the evaporated first AF material 130 through the polyimide material 116.

[0026] Fig. Figure 9 is an illustrative flowchart depicting various processes for carrying out methods according to the invention. It is understood that the various methods described here can be implemented in alternative configurations, in a different sequence, with additional steps, and / or by omitting one or more steps. Using the methods of the invention, various structures can be formed in the first region R1 of the IC structure 100, and such structures can be processed (e.g., converted into cavities) for authentication using an authentication plan or a similar solution for verifying the location of cavities in a structure.

[0027] With reference to Fig. 2 and Fig. 9. The methods according to the invention can include process P1, in which one or more regions of the first AF material 130 are formed in the IC structure 100, e.g. in the polyimide material 116 (or alternatively in the metal wiring layer(s) 102 (e.g. as in Fig. 7, Fig. 8 shown). The first AF material 130 formed in process P1 can be located in electrically inactive sections of the IC structure 100, i.e., in the first region R1, which is physically and electrically separated from the LI conductor(s) 118 or other active elements in the second region R2. In some embodiments, several regions of the first AF material 130 can be formed in a pattern 132 such that the arrangement of the first AF material 130 is visually identifiable (e.g., a series of symbols including shapes, letters, etc.). At the end of process P1, the first AF material 130 may be visually indistinguishable from the material in which it is formed (e.g.,Polyimide material 116, ILD layer(s) 112 and / or other insulating structures), since it is formed from an essentially transparent material such as an oxide, a carbon-based ERF material and / or any material with a refractive index similar to that of dielectric materials.

[0028] With reference to Fig. 4 and Fig. 9. The methods of the invention can perform process P2 of the conversion of the first AF material 130 ( Fig. 1, Fig. 2) into one or more cavities 140 within the IC structure 100. The conversion in process P2 may, for example, include heating the IC structure 100 to a temperature sufficient for the evaporation of organic-based ERF materials (e.g., at least about 300 °C) using an external UV heat source and / or other types of heat sources. The first AF material 130 located in the metallic wiring layer(s) 102 may pass through pores in the polyimide material 116 or, if applicable, through the opening(s) 150 ( Fig. 7, Fig. 8) evaporate. In further embodiments, the conversion in process P2 can include etching the first AF material 130 to form one or more cavities 140 without etching or otherwise removing any other material located adjacent to or beneath the first AF material 130. The cavity (cavities) 140 formed by removing the first AF material 130 may be optically distinct from the polyimide material 116, the ILD layer(s) 112, or other adjacent materials, for example, by being composed of gas and thus having a different refractive index. Cavities 140 are optically detectable by microscopy in other processes described herein.

[0029] With regard to the Fig. 6 and Fig. 9. The methods according to the invention may optionally include an additional process P3 for forming a second AF material 144 within the cavity(s) 140. The formation of the second AF material 144 may include a second deposition of carbon-based ERF material, oxide material, etc., in selected sections of the cavity(ies) 140, without forming a second AF material 144 at other locations. In some embodiments, process P3 may be integrated into process P2, e.g., by converting only some parts of the first AF material 130 ( Fig. 1, Fig. 2) into the cavity(ies) 140, while the remaining parts of the material become the second AF material 144. At the end of process P2 or P3, a pattern 142 can be formed in the IC structure 100, wherein the pattern 142 contains the cavity(ies) 140 or a combination of the cavity(ies) 140 and the second AF material 144. Furthermore, the pattern 142 can be physically and electrically isolated from the electrically active components in the second region R2 of the IC structure 100 (e.g., LI conductor 118) and thus have no operational effect on the IC structure 100.

[0030] Methods according to the invention can include process P4 for generating an authentication plan of the IC structure 100. The authentication plan generated in process P4 can include a visual representation, a set of coordinates, and / or other references indicating the location of one or more cavities 140 in the IC structure 100. The position of the one or more cavities 140 in the authentication plan can include a pattern 142. In some cases, the authentication plan can include the pattern 142 with both the cavity(ies) 140 and the second AF material 144, and it can additionally or alternatively include the pattern 142 without the second AF material 144. In further implementations, process P4 can include generating multiple authentication plans, each of which can correspond to different states of the IC structure 100, such as...Pattern 142 with second AF material 144, pattern 142 with only one or more cavities 140, etc. The authentication plan created in process P4 may take the form of computer program code stored on a non-transferable storage medium and may therefore be transmitted to other parties via the Internet or other solutions for transferring data from one entity to another.

[0031] The methods of the invention can be particularly efficient in detecting whether intermediate recipients of the IC structure 100 in a supply chain have manipulated the IC structure 100. Such manipulation can bring the IC structure 100 to a temperature at which the first AF material 130 ( Fig. 1, Fig. 2) or the second AF material 144 is evaporated, and / or other types of processing that may inadvertently remove parts of the first AF material 130 or the second AF material 144. Such processing may increase the number of cavities 140 and / or alter the pattern 142, thus causing the IC structure 100 to differ from its authentication plan. The method P5 according to the invention may include transferring the IC structure 100 to one or more recipients, e.g., an intended user of the product. The transfer of the IC structure 100 may be made directly from the manufacturer to a customer and / or via one or more intermediate recipients, such as sub-manufacturers, carriers, etc., in a supply chain for the product. A process P6, which may take place before, during, or after a process P5, may include providing one or more authentication plans to one or more recipients of the IC structure 100.The provision of the authentication plan can, for example, involve the electronic transmission of the authentication plan as data from one entity (e.g., the manufacturer of the IC structure 100) to another (e.g., the eventual customer). In some cases, e.g., if the customer already possesses the IC structure 100 and / or its authentication plan(s), processes P5 and P6 may be omitted.

[0032] A process P7 in the method according to the invention can include authenticating the IC structure 100 based on the authentication plan(s) created in process P4. The authentication process P7 can include optical inspection of the IC structure 100 using a microscope and / or other imaging techniques. For example, process P7 can include optical inspection of the IC structure 100 and authentication of the IC structure 100 by verifying whether the position of the cavity(ies) 140 and / or the shape of the pattern 142 therein corresponds to the authentication plan in process P4. In another example, the receiver of the IC structure 100 can authenticate the IC structure 100 by heating it to an evaporation temperature as described herein and then comparing the location of the cavity(ies) 140 and / or the pattern 142 in the IC structure 100 with the authentication plan.If the location of cavity(s) 140 and / or pattern 142 matches the authentication plan, the IC structure 100 is considered authentic. In cases where the location of cavity(s) 140 and / or pattern 142 does not match the authentication plan, the IC structure 100 is considered non-authentic (e.g., manufactured by another entity, tampered with, and / or otherwise not in accordance with its original specification). In either case, the procedure can be completed (“Done”), and the recipient can use the IC structure 100 or, if appropriate, notify the manufacturer.

[0033] Embodiments of the invention offer several technical and commercial advantages, some of which are discussed here by way of example. As can be seen from the foregoing, embodiments of the invention make it possible to fabricate the IC structure 100 with built-in authentication features, thereby enabling the IC structure 100 to be optically authenticated without special equipment (e.g., imaging tools other than microscopes). Embodiments of the invention also ensure that the authentication features (e.g., cavity(s) 140 and / or pattern 142) or parts thereof are undetectable until a predetermined event occurs, e.g., raising the temperature of the IC structure 100 to vaporize the target materials, etching oxide(s) over a mask, etc. This is achieved by using AF materials that are optically indistinguishable from adjacent materials (e.g., polyimide materials, dielectric layers, etc.).), it may be impossible or impractical for third parties who are not the recipient to detect the AF materials. Furthermore, it may be difficult or impossible for third parties to modify and / or manipulate the IC structure 100 without inadvertently damaging AF materials (e.g., the first AF material 130 (). Fig. 1, Fig. 2) to convert into cavities 140.

[0034] Aspects of the present invention are described above with reference to flowchart representations and / or block diagrams of methods, devices (systems), and computer program products according to the embodiments of the invention. It is understood that each block of the flowchart representations and / or block diagrams, and combinations of blocks in the flowchart representations and / or block diagrams, can be implemented by computer program instructions.These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or any other programmable data processing device to create a machine such that the instructions executed through the processor of the computer or other programmable data processing device provide means for implementing the functions / actions specified in the flowchart and / or block diagram block or blocks.

[0035] The structure and process described above are used in integrated circuit chips. The resulting integrated circuit chips can be distributed by the manufacturer in the form of raw wafers (i.e., a single wafer containing multiple unhoused chips), as bare chips, or in housed form. In the latter case, the chip is mounted in a single-chip package (e.g., a plastic substrate with leads attached to a motherboard or other higher-level carrier) or in a multi-chip package (e.g., a ceramic substrate with surface contacts and / or buried contacts). In each case, the chip is then integrated with other chips, discrete circuit elements, and / or other signal processing devices as part of either (a) an intermediate product, such as a motherboard, or (b) a final product.The end product can be any product containing integrated circuit chips, ranging from toys and other simple applications to sophisticated computer products with a screen, keyboard or other input device and a central processing unit.

[0036] The terminology used herein serves only to describe certain embodiments and is not to be construed as limiting the invention. The singular forms "a" and "the" also include the plural forms unless the context clearly indicates otherwise. Furthermore, it is understood that the terms "comprises" and / or "comprehensive," when used in this description, specify the presence of certain features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. "Optional" means that the event or circumstance described below may or may not occur, and that the description includes cases in which the event occurs and cases in which it does not.

[0037] Indefinite formulations, such as those used here in the description and claims, may be used to modify any quantitative representation that may permissibly vary without altering the fundamental function to which it refers. Accordingly, a value modified by one or more terms such as "approximately," "approximately," and "essentially" is not limited to the exact value stated. At least in some cases, the indefinite formulation may correspond to the accuracy of an instrument used to measure the value. Here, and throughout the specification and claims, range boundaries may be combined and / or interchanged; such ranges are identified and include all subranges contained therein unless the context or language indicates otherwise.The term "approximately", when applied to a specific value within a range, refers to both values ​​and, unless otherwise specified depending on the accuracy of the measuring instrument, may mean + / - 10% of the stated value(s).

Claims

[1] Method for authenticating an IC structure (100), wherein the method comprises: a formation of a first authentication film material (130) within the IC structure (100), wherein the composition of the first authentication film material (130) differs from an adjacent material within the IC structure (100), wherein the first authentication film material (130) is formed in a part of a wiring layer (102) of the IC structure (100) under a polyimide layer, wherein the part of the wiring layer (102) has at least one opening (150) through the polyimide layer dimensioned for the evaporation of the first authentication film material (130); a conversion of the first authentication film material (130) into a cavity (140) within the IC structure (100); and a generation of an authentication plan of the IC structure (100), wherein the authentication plan includes a location of the cavity (140) in the IC structure (100) for authentication of the IC structure (100). [2] Method according to claim 1, wherein the formation of the first authentication film material (130) comprises forming the first authentication film material (130) within a polyimide layer of the IC structure (100) in an area that is horizontally remote from at least one electrically active element in the IC structure (100). [3] Method according to claim 1, wherein the conversion of the first authentication film material (130) into the cavity (140) comprises evaporating the first authentication film material (130). [4] Method according to claim 1, further comprising forming a second authentication film material (130, 144) within the IC structure (100), wherein at least a part of the cavity (140) does not include the second authentication film material (130, 144) and the authentication plan further comprises a position of the second authentication film material (130, 144) in the IC structure (100). [5] Method according to claim 4, wherein forming the second authentication film material (130, 144) comprises an uneven distribution of the second authentication film material (130, 144) in the cavity (140). [6] Method according to claim 1, wherein the first authentication film material (130) comprises a carbon-based energy degradation film. [7] Method according to claim 1, further comprising providing the authentication plan to a receiver of the IC structure (100). [8] Integrated IC structure (100), comprising: a polyimide layer; a metal wiring layer (102) beneath the polyimide layer, wherein the metal wiring layer (102) has a first region with at least one electrically active element and a second region horizontally removed from the at least one electrically active element; a cavity (140) in the second region of the metal wiring layer (102), wherein a location of the cavity (140) within the metal wiring layer (102) defines an authentication pattern (132, 142) for the IC structure (100); an authentication film material in the second region of the metal wiring layer (102), wherein the authentication pattern (132, 142) for the IC structure (100) further comprises a location of the authentication film material (130); and comprising at least one opening (150) through the polyimide layer to the metal wiring layer (102), wherein the at least one opening (150) is dimensioned for the evaporation of the authentication film material (130). [9] IC structure (100) according to claim 8, wherein a location of the cavity (140) is optically detectable from outside the IC structure (100) to enable authentication of the IC structure (100). [10] IC structure (100) according to claim 8, wherein the authentication film material (130) comprises a carbon-based energy dissipation film. [11] IC structure (100) according to claim 8, wherein the authentication film material (130) is unevenly distributed within the cavity (140).

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