Browse Prior Art Database

Extracting Separating and Characterizing Ions of Unreacted (Active) Chemicals on Electronic Components

IP.com Disclosure Number: IPCOM000082457D
Original Publication Date: 1974-Dec-01
Included in the Prior Art Database: 2005-Feb-28
Document File: 2 page(s) / 46K

Publishing Venue

IBM

Related People

Corl, EA: AUTHOR [+3]

Abstract

Epoxy encapsulants may contain a number of chemicals such as phenols, amines, halogenated hydrocarbons, and acids such as HBr and HCl. Even though they are in the order of low parts per million or less, if sufficiently mobile on the electronic component (package) they may react with the chip and package metallurgy to cause corrosion. It is important to determine the ionic characteristics of each of the active chemical fractions, in order to control and study the degradation of microcircuits.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 71% of the total text.

Page 1 of 2

Extracting Separating and Characterizing Ions of Unreacted (Active) Chemicals on Electronic Components

Epoxy encapsulants may contain a number of chemicals such as phenols, amines, halogenated hydrocarbons, and acids such as HBr and HCl. Even though they are in the order of low parts per million or less, if sufficiently mobile on the electronic component (package) they may react with the chip and package metallurgy to cause corrosion. It is important to determine the ionic characteristics of each of the active chemical fractions, in order to control and study the degradation of microcircuits.

This technique uses a combination of solvent extraction, gas chromatography, and conductivity detection to determine the ionic characterization of the active chemical fractions.

The first step is to place the package in an extractor for a period of from a few hours to twenty-four hours. Fig. 1 shows a Soxlet extractor with a suitable solvent 8, which impinges on package 10 as liquid and vapor, while extracting the highly mobile, soluble chemicals and collecting them in the extracting solvent. The extracted chemicals are then separated using gas chromatography; however, the ionic characteristics of the fractions leaving exhaust tube 12 are still not apparent.

In the next step, as shown in Fig. 2, the fractions are fed directly from the gas chromatograph into a conductivity cell, which consists of a stainless steel detector 14, plus and minus electrodes 16, a solvent exit tube...