Chemical use in the semiconductor manufacturing industry

Abstract

Background:The semiconductor industry is known to use a number of chemicals, but little is known about the exact chemicals used due to the ingredients being kept as a trade secret. Objectives: The objective of this study was to analyze chemical use using a safety data sheet (SDS) and chemical inventory provided by a major semiconductor company, which operated two factories (A and B). Methods: Descriptive statistics were obtained on the number of chemical products and ingredients, photoresists, and carcinogens, classified by the International Agency for Research on Cancer (IARC), as well as trade secret ingredients. The total chemical use per year was estimated from chemical inventories mass (kg). Results: A total of 428 and 432 chemical products were used in factories A and B, respectively. The number of pure chemical ingredients, after removing both trade secret ingredients and multiple counting, was 189 and 157 in factories A and B, respectively. The number of products containing carcinogens, such as sulfuric acid, catechol, and naphthalene was 47/428 (A) and 28/432 (B). Chemicals used in photolithography were 21% (A) and 26% (B) of all chemical products, and more than 97% among them were chemicals containing trade secret ingredients. Conclusions: Each year, 4.3 and 8.3 tons of chemicals were used per person in factories A and B, respectively. Because of the high level of commercial secrecy and the use of many unregulated chemicals, more sustainable policies and methods should be implemented to address health and safety issues in the semiconductor industry.

Green Nanofabrication Opportunities in the Semiconductor Industry: A Life Cycle Perspective

“…These ever-evolving dynamics make it challenging to accurately assess environmental health and safety concerns in the industry [ 33 ]. It is also hard to obtain information on the number and volume of chemicals used in the actual semiconductor factories [ 200 ]. To address ESH/S challenges, it is important to understand the actual chemical usage in the industry.…”

“…The reduced number of steps and avoidance of UV exposure and photomasks however suggests a possibly more efficient process with reduced environmental toxicity. It is also worth considering that precise environmental impact of photoresists and photostripper is challenging to determine as a result of trade secrets [ 200 ]. Thus the exact environmental threat of photoresist and photostripper compared to materials used in BCP and polymer brush lithography may be challenging to determine.…”

“…An example can be found in the work by Schischke et al, where they outline a questionnaire to guide the process of data collection for employees of the fab and infrastructure facilities in collecting the data [ 181 ]. Chemical information provided by a company for the mature deposition technology data set could include chemical information on the phase, product number, factory, chemical product (e.g., photoresist), ingredients, chemical abstract service (CAS) number, processes used, number of units and the pattern of usage [ 200 ].…”

Chemical Use and Associated Health Concerns in the Semiconductor Manufacturing Industry

“…It is clear that large amounts of chemicals have been used, replaced, and introduced continuously for more efficient and improved production of semiconductors [ 1 , 5 , 6 , 21 , 23 ], such that the cliché “the cleanroom is not clean” may be appropriate for chemical use and the related issue of environmental and occupational disease [ 20 ]. Although hundreds of chemical products are used in the workplace, the true extent has yet to be revealed [ 5 ].…”

“…The semiconductor industry itself also has concerns, leading to the introduction of key environmental priority indicators [ 24 , 25 ], but data about chemical use are very limited. In 2018, the use of chemicals at the one semiconductor industry was reported by our research group, and in 2019, a more detailed description of chemical uses in the photolithography process [ 23 , 26 ] The first study reported that more than 150 chemical constituents were used in more than 450 chemical products, more than 40% of which contained trade secrets and that safety and health information was very limited. In second study, we found that more than 90% of the chemicals in the photolithography process contain trade secrets, safety data sheets (SDSs) provides inadequate safety and health information, and has found that by-products such as benzene and formaldehyde may be produced at the photolithography process; however, no comprehensive study on the use of chemical products in the workplace exists.…”