TABLE OF CONTENTS Electronics manufacturing and disposal of electronics products are perturbing the equilibrium of the atmosphere-land-ocean system on earth. While microelectronics improves the global standard of living, its environmental impact poses a major threat to the quality and existence of life on earth. In the past century, the major concern was pollution from the automobile industry, the steel industry, and energy production using coal. The harmful effects of combustion engine emission made the problem even worse. This is further aggravated by the present impact from the electronics manufacturing industry. These cumulative effects have brought the environment to such a level that clean water and air can no longer be guaranteed.
Regarding environmental concerns about microelectronics, in addition to the use of lead in solder materials, which has been a well-known issue, the other significant aspect is the use of bromine and antimony-containing flame retardants in printed circuit boards (PCBs) and in area-array package substrates. These flame retardants are based on a combination of bromine and antimony oxide. Halogens, including bromine, are only weak fire retardants, and antimony oxide by itself is not a fire retardant; however, when combined, they become very effective. The combination retards flames in two ways. During burning, antimony oxide promotes the formation of char (essentially, carbon), which reduces the formation of volatile gases. At the same time, the heat of initial combustion promotes a cross-linking between the organic compound and the antimony, which results in a more stable thermoset polymer. In addition, at temperatures above...
