Laser trimming of circuit elements on semiconductive substrates
AssigneeAnalog Devices, Inc.
InventorsJerome F. Lapham, Tommy D. Clark
Life of this patent
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Abstract
A method of laser trimming thin film resistors on semiconductive substrates wherein the laser is set to a frequency equal to or less than E.sub.g /h, where E.sub.g is the optical band-gap energy of the doped semiconductor substrate, and h is Planck's constant.
Claims7
The method of laser trimming of elements on a doped semiconductive substrate, wherein a laser beam is directed onto the element from the side of the substrate carrying the element and is so controlled as to vaporize or otherwise remove or alter the material of the element so as to achieve a predetermined electrical characteristic for the element;
- said method further comprising the step of setting the frequency of the laser at a value no greater than E.sub.g /h, where E.sub.g is the optical band-gap energy of the doped substrate and h is Planck's constant.
The method of laser trimming of elements on a doped semiconductive substrate, wherein a laser beam is directed onto the element from the side of the substrate carrying the element and is so controlled as to vaporize or otherwise remove or alter the material of the element so as to achieve a predetermined electrical characteristic for the element;
- said method comprising the step of setting the laser to operate at a wavelength producing photons having an energy less than the optical band-gap energy of the doped substrate.
Dependencies are inferred from the claim text.