Abstract: A Radio Frequency Identification (RFID) IC may have raised contact islands that include conductive contact pads covering a repassivation layer. The raised contact islands are formed by removing part or all of the repassivation material surrounding the raised contact islands. The repassivation material that is not covered and protected by the contact pads may be removed by a strip process that also removes a masking layer used for IC etching. Singulated RFID ICs may be assembled into an RFID tag using a B-stage adhesive that is applied to the ICs and then partially cured. The ICs are deposited onto preheated inlays. The preheated inlays cause the B-stage adhesive on the ICs to bind to the inlays.

Abstract: Technologies are generally directed to assembly of a Radio Frequency Identification (RFID) tag precursor. An assembly may be provided, the assembly having an RFID integrated circuit (IC), a nonconductive repassivation layer on a surface of the IC and confined within a perimeter of the surface, and a conductive redistribution layer on the repassivation layer and confined within the perimeter of the surface, in which a first portion of the redistribution layer is electrically connected to the IC through a first electrical connection. A substrate having a first antenna terminal to the assembly may be attached with an adhesive, and at least a first portion of a nonconductive barrier present on at least one of the first antenna terminal and the first portion of the redistribution layer may be reacted with a reactant to make the first portion of the nonconductive barrier conductive.

Abstract: An RFID IC assembly having a repassivation layer and a conductive redistribution layer may be assembled onto a tag substrate with an additional layer. The additional layer includes one or more etchants for creating an opening in a nonconductive barrier layer between the assembly and the substrate, and may also include an adhesive for attaching the assembly to the substrate.

Abstract: An RFID tag possesses a group key issued by an authorized entity. When a reader requests some information from the tag, such as an identifier, the tag transmits a random number to the reader. The tag then determines one or more reader characteristics based on a response received from the reader. In one embodiment, the tag generates a verification value based on the random number and the group key and compares the verification value to the received response. If the comparison succeeds, the tag may treat the reader as possessing particular functionality, authorized to implement a particular feature, and/or authorized to receive information from the tag. If the comparison fails, the tag may treat the reader as lacking particular functionality, not authorized to implement a particular feature, and/or not authorized to receive information from the tag. The tag may request additional response(s) from the reader before determining the reader characteristic(s).

Abstract: Methods and systems are described for authorizing an item with an RFID tag to leave a facility. In one embodiment, a mobile device receives or determines an exit code (EC) to write into the tag in response to providing authorizing information. The EC may be based on information stored in the tag such as the tag's item identifier or other tag information (collectively an item identifier or II), a ticket value, other information such as the OC, a mobile identity or location, or any other suitable information. Upon verification of the EC, the tagged item is allowed to leave the facility. In another embodiment, the mobile device stores an item identifier (II) associated with the tag and provides authorizing information. Upon verifying the authorizing information and confirming that the stored II corresponds to the tagged item's II, the tagged item is allowed to leave the facility.

Abstract: An assembly having an RFID integrated circuit (IC), a nonconductive repassivation layer on a surface of the IC and confined within a perimeter of the surface, and a conductive redistribution layer on the repassivation layer and confined within the perimeter of the surface may be provided. At least a first portion of the redistribution layer may be electrically connected to the IC through a first opening in the repassivation layer. Furthermore, a substrate having a first antenna terminal may be provided, and a second opening may be formed in a nonconductive barrier present on at least one of the first antenna terminal and the first portion of the redistribution layer with an etchant. The first opening and the second opening may be nonoverlapping. The assembly may be attached to the substrate with an adhesive.