Patent ID: 8207478

Claim:
A method for rapid heating of materials, the method comprising: providing an apparatus including a variable high frequency microwave power source, a microwave heating head, and a measurement and control system, wherein the microwave heating head includes a heating head coupler for coupling microwaves to a material to be heated and an electronic match-up network including inductive (L) components and capacitive (C) components for tuning a resonant frequency and an impedance of the heating head coupler; selecting an appropriate heating head, based on a type of material to be heated, wherein the selecting an appropriate heating head includes: selecting an inductive coil as the heating head, when the type of material to be heated includes one of high conductive thin films and semiconductors; and selecting two capacitive electrodes as the heating head, when the type of material to be heated includes one of dielectric material, glass and ceramics; placing the material to be heated at a position proximal to the selected heating head, thus loading the heating head such that the material to be heated is maximally exposed to a microwave power from the heating head; electronically adjusting the microwave power source and the L and C parameters of the match-up network so that a characteristic frequency and an impedance of the loaded heating head are optimally matched with a characteristic frequency and an impedance of the microwave power source such that the microwave power from the heating head is focused upon selected portions of the material to be heated; generating microwaves within the microwave power source; applying the microwave power to the material to be heated, thus heating the material; adjusting the microwave power source and the heating head during heating of the material so as to compensate for any frequency and impedance shifting of the heating head caused by a temperature change in the material during heating; and controlling a microwave power waveform to heat the material to a predetermined heating temperature at a predetermined heating rate using the measurement and control system; wherein the apparatus is capable of achieving a heating rate of 10-2000° C./second for high conductive films and semiconductors and does not heat the material in a microwave cavity; and wherein the microwave power source can sweep a predetermined bandwidth within a frequency range from 300 MHz to 20 GHz.