Reduced cycle time manufacturing processes for thick film resistive devices
A process of forming a resistive device such as a load resistor or a heater is provided that includes forming a dielectric layer onto a substrate, a target, or an adjacent functional layer, wherein the dielectric layer in one form defines a single layer of dielectric tape. The dielectric tape is laminated to the substrate, the target, or the adjacent functional layer through a single predetermined cycle of pressure, temperature and time, and then a resistive layer is farmed on the dielectric layer, and a protective layer is formed over the resistive layer.
1. A process of forming a thick film material onto a tubular target for use in a resistive device, the thick film material including at least one layer of dielectric, which does not exhibit adhesiveness and is capable of being repositioned multiple times prior to laminating the at least one layer of dielectric to the tubular target, and the thick film material being laminated and formed to the tubular target, the process comprising:
placing a first bladder proximate at least one surface of the tubular target and inside the tubular target;
inflating the first bladder such that the first bladder engages one of the thick film material and the tubular target to clench the tubular target;
moving the first bladder with the tubular target to a second bladder such that another surface of the tubular target is disposed proximate the second bladder and the second bladder is disposed around the tubular target;
inflating the second bladder such that the second bladder engages the other one of the thick film material and the tubular target; and
maintaining the inflation of the first bladder and the second bladder through a single predetermined cycle of pressure, temperature and time, such that the layer of dielectric is laminated to the tubular target with a substantially uniform thickness and adhesion,
wherein the first bladder is separate from the second bladder and moveable relative to the second bladder.
2. The process according to claim 1 , wherein the thick film material comprises a single layer of dielectric tape.
3. The process according to claim 2 , wherein the single layer of dielectric tape defines a base dielectric layer that is laminated to a substrate.
4. The process according to claim 2 , wherein the single layer of dielectric tape defines a resistive layer that is laminated to one of: a base dielectric layer and the target.
5. The process according to claim 2 , wherein the single layer of dielectric tape defines a protective layer that is laminated to a resistive layer.
6. The process according to claim 1 , wherein the thick film material comprises a preform defined by a dielectric tape and a resistive element disposed on the dielectric tape.
7. The process according to claim 1 , wherein the thick film material comprises a preform defined by a dielectric tape, a resistive element disposed on the dielectric tape, and conductors disposed on the dielectric tape and in electrical contact with the resistive element.
8. The process according to claim 1 , wherein the thick film material comprises a preform defined by a dielectric tape, a resistive element disposed on the dielectric tape, conductors disposed on the dielectric tape and in electrical contact with the resistive element, and a protective layer of dielectric tape disposed over the resistive element and not over the conductors.
9. The process according to claim 1 , wherein the thick film material comprises a preform defined by a protective layer of dielectric tape and a resistive element disposed onto the protective layer of dielectric tape.
10. The process according to claim 1 , wherein the thick film material comprises a preform defined by a protective layer of dielectric tape, a resistive element disposed onto the protective layer of tape, and conductors in electrical contact with the resistive element, wherein the protective layer of dielectric tape defines apertures through which the conductors are exposed.