The present invention relates generally to advanced smart cards that may contain batteries, LEDs, LCDs, polymer dome switches, fingerprint sensors, and other electronic components that are not found in conventional smart cards. A conventional smart card is the size of a traditional credit card, and they usually contain an Integrated Circuit (IC) chip and may contain an antenna if the card must transfer data using Radio Frequency (RF) transmission. Advanced smart cards may include components that are not found in conventional smart cards, such as batteries, displays, and keypads. Advanced smart cards may therefore be capable of many sophisticated functions, such as displaying data, enabling users to enter Personal Identification Numbers (PIN) and passwords, and detecting security threats.
Smart cards are being widely utilized for access control systems, storage of biometric data, national border control, and in many other applications. Smart cards typically contain information about a user. For example, the U.S. Department of Defense (DoD) Common Access Card (CAC) project requires a contactless chip to contain biometric data about a citizen including a digitized portrait and fingerprint data.
These advanced smart cards typically consist of a multi-layer structure having one or more plastic layers surrounding integrated circuits that store the data. Data is transferred to and from the cards through radio frequency (RF) transmission. Cards that transfer data only by RF transmission are so-called “contactless” cards. For RF transmission, contactless advanced smart cards include an antenna for transmitting data to and from the integrated circuits. With increasing security concerns in the post-September 11 environment, contactless RFID chips are being incorporated into documents like passports and other document or note formats.
Several problems exist with prior art smart card arrangements in that PVC is utilized for its rigidity in order to protect the antenna and integrated circuit from breaking upon flexure. Each layer of PVC must be of a prescribed thickness to surround and protect the components. In order to maintain the rigidity required and house the components necessary, these PVC cards tend to be relatively thick as compared to other types of cards such as a credit card. Generally, such resulting multi-layer structures are approximately 0.060 inches thick. Additionally, PVC tends to become brittle with age and exposure to ultraviolet rays. This contributes to card failure in time. Additionally, specialized printing equipment is required to print information on the outer surfaces of the PVC material.
Many other problems frequently occur with the very high temperatures and pressures required for hot lamination including damage to fragile Integrated Circuit (IC) chips, antenna (often thin wire coils, thinly etched copper, or thinly deposited silver), and other electronic components. The very high heat levels, typically about 300° F., and the very high pressures, typically ranging from 1,000 to 30,000 PSI or greater, used in the plastic card lamination production process are the cause of severe thermal and physical stress on smart card components.
What is needed is an improved method for producing an Advanced Smart Card (containing Integrated Circuits, antennae, batteries, polymer dome switches, Liquid Crystal Displays, Light Emitting Diode arrays, fingerprint sensors), that allows sensitive components to be securely and reliably incorporated into a very thin and flexible card structure, and that utilizes low heat (e.g. less than 150° F.) and low pressure (e.g. less than 100 PSI).
A new generation of highly sophisticated smart cards has become technically feasible due to advances in materials science and electronics. Miniature batteries, data displays, keypads, and even fingerprint sensors have been developed that may be incorporated into a smart card sized form factor. These advances are stimulating new smart card capabilities and applications. For example, a smart card equipped with a battery, data display, and keypad would enable users to view data regarding: 1) the current balance of electronic purse applications, 2) recent credit card transaction information, or 3) bank account balance information. These capabilities could also be utilized to enhance security with password-enabled credit card functions. While these expanded smart card capabilities offer tremendous potential for new applications, large scale production of advanced cards with lamination-based manufacturing techniques is extremely difficult due to the electronic component damage caused by the high heat and pressure used in lamination. A new card production process utilizing low heat and pressure is needed to enable delicate electronic components to be effectively incorporated within card bodies.