CONTROL OVER HYDROGEN FLUORIDE LEVELS IN OXIDE ETCHANT

摘要

The invention is directed towards methods and compositions for identifying the amount of hydrofluoric acid in a buffered oxide etching composition. In buffered oxide etching compositions it is very difficult to measure the amount of hydrofluoric acid because it has varying equilibriums and it is toxic so it hard to handle and sample. When used to manufacture microchips however, incorrect amounts of hydrofluoric acid will ruin those chips. The invention utilizes a unique method of spectrographically measuring the hydrofluoric acid when in contact with added chromogenic agents to obtain exact measurements that are accurate, immediate, and safe.

主权项

1. A method of detecting and measuring the presence of ammonium fluoride in a BOE composition, the method comprising the steps of:
collecting a representative sample of a BOE composition, adding a chromogenic agent to the composition, performing a spectrometric measurement of the composition, comparing the spectrometric measurement to pre-determined values to identify the quantity of ammonium fluoride in the BOE composition.