Abstract

There is described a method for stabilizing a post-trimming resistance of a thermally isolated electrical component made from a thermally mutable material, the method comprising: generating at least one heating pulse, the at least one heating pulse having an initial amplitude corresponding to a trimming temperature, a slope corresponding to a given cooling rate and a duration corresponding to a given cooling time; and applying the at least one heating pulse to one of the thermally isolated electrical component and a heating device in heat transfer communication with the thermally isolated electrical component, after a trimming process, in order to cause the electrical component to cool in accordance with the given cooling rate, the given cooling rate being slower than a passive cooling rate determined by the thermal isolation of the electrical component

IPC Classes  ?

• H01C 13/00 - Resistors not provided for elsewhere
• H01C 17/22 - Apparatus or processes specially adapted for manufacturing resistors adapted for trimming
• H01L 21/02 - Manufacture or treatment of semiconductor devices or of parts thereof

Abstract

A method for arranging a plurality of thermally isolated microstructures over at least one cavity, each of the microstructures housing at least part of a thermally-trimmable resistor, the thermally-trimmable resistor having at least a functional resistor, the method comprising: providing pairs of facing microstructures; grouping together sets of pairs of facing microstructures, each of the sets having at least one pair of facing microstructures; and arranging microstructures within a given set to have each microstructure exposed to heat from a same number of facing, side, and diagonal neighbors of microstructures from a same resistor.

IPC Classes  ?

• H01C 17/22 - Apparatus or processes specially adapted for manufacturing resistors adapted for trimming

Abstract

There is described a method to change the value of a thermally-trimmable resistor in a non-permanent way by raising the temperature of the thermally- trimmable resistor to a level that is somewhere between room temperature and trimming temperature. By doing this, the trimming range that is available via true thermal trimming may be explored without actually trimming the value of the resistor. This is possible when the thermal Iy- trimmable resistor, or a portion thereof, has an essentially non-zero temperature coefficient of resistance (TCR).

IPC Classes  ?

• G01R 31/30 - Marginal testing, e.g. by varying supply voltage
• G01R 31/316 - Testing of analog circuits
• H05K 13/00 - Apparatus or processes specially adapted for manufacturing or adjusting assemblages of electric components
• H01C 7/02 - Non-adjustable resistors formed as one or more layers or coatingsNon-adjustable resistors made from powdered conducting material or powdered semi-conducting material with or without insulating material having positive temperature coefficient
• H01C 7/04 - Non-adjustable resistors formed as one or more layers or coatingsNon-adjustable resistors made from powdered conducting material or powdered semi-conducting material with or without insulating material having negative temperature coefficient

Abstract

The thermal isolation of a thermally-trimmable resistor has a direct impact on temperature rise. It is possible to design the thermal isolation of the portions of a compound resistor to minimize or optimize the resistance variation of the overall compound resistor. The resistance variation of the overall compound resistor due to self-heating of its portions can be reduced or optimized, by designing different thermal isolation for each of the portions, such that compensation and/or optimization can occur. Furthermore, one can also design such different thermal isolation of the portions of a compound resistor to minimize resistance variation over a trim range of a compound resistor due to self-heating.

IPC Classes  ?

• H01C 17/232 - Adjusting the temperature coefficientAdjusting value of resistance by adjusting temperature coefficient

Abstract

A compound resistor is used to compensate for trimming induced shift in temperature coefficient of resistance of a trimmable resistor. The compound resistor is composed of a first and second portion, at least one of the two portions being thermally trimmable, and the parameters for the first and second portion are selected such that the trimming induced shift can be minimized on an overall resistance and temperature coefficient of resistance of the compound resistors by trimming the trimmable resistor.

IPC Classes  ?

• H01C 17/232 - Adjusting the temperature coefficientAdjusting value of resistance by adjusting temperature coefficient

Abstract

A circuit for trimming a thermally-trimmable resistor, measuring a temperature coefficient of resistance of the thermally-trimmable resistor, and annealing a thermally-trimmable resistor post-trimming, the circuit comprising: a thermally-isolated area on a substrate housing the thermally-trimmable resistor; heating circuitry for applying a signal to a heating resistor; and a constant-power module adapted to maintain power dissipated in the heating resistor substantially constant over a duration of the signal by varying at least one parameter of the signal as a result of a change in resistance of the heating resistor during the signal.

IPC Classes  ?

• H01C 17/22 - Apparatus or processes specially adapted for manufacturing resistors adapted for trimming
• H01C 17/232 - Adjusting the temperature coefficientAdjusting value of resistance by adjusting temperature coefficient
• H01L 21/64 - Manufacture or treatment of solid-state devices other than semiconductor devices, or of parts thereof, not specially adapted for a single type of device provided for in subclasses , , or