US EPA

1032533 

Journal Article 

Reaction of gallium arsenide with concentrated acids: formation of arsine 

Scott, N; Carter, DE; Fernando, Q 

1989 

Yes 

American Industrial Hygiene Association Journal
ISSN: 0002-8894 

NIOSH/00189225 

50 

7 

379-381 

English 

2756869 

10.1080/15298668991374831 

WOS:A1989AE48700008 

Crystalline particles of gallium arsenide (GaAs) (approximately 2 microns in diameter) react with concentrated hydrochloric acid (HCl) (11.6 to 9 M) to form highly toxic arsine (AsH3) gas. None of the other strong acids that were investigated reacted with gallium arsenide to form AsH3. A spectrophotometric method, based on the reaction of AsH3 with silver diethyldithiocarbamate in a chloroform solution containing morpholine, was used to detect AsH3 gas dissolved in aqueous solutions and to determine the AsH3 gas that was liberated by the reaction of GaAs with HCl. Active sites on the gallium arsenide surface initiate the reaction that forms AsH3 gas. Absorption of oxygen or ions from solution on these active sites inhibits the formation of AsH3. 

DCN-184640; Analytical methods; Chemical analysis; Analytical chemistry; Semiconductors; Electronics industry; Toxic gases; Gas detectors; Gas sampling