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Semiconductor-manufacturing companies often portray their fabrication facilities as being clean,environmentally friendly, and conspicuously free of the black, billowing smokestacks that have come to be associated with theplants and factories of other major industries. These facilities produce no visible pollution and certainly do not appear to poseany health or environmental risks.

In truth, the term “clean room,” itself is more than just a bit of an understatement. Industry executivesoften boast that their clean rooms are from 1,000 times to 10,000 times cleaner and more sanitary than any hospital operatingroom.

What are the health risks involved in the semiconductor industry?

The use of sterile techniques and the fastidious attention devoted to cleanliness in the semiconductorindustry may perpetuate the illusion that the manufacturing of semiconductors is a safe and sterile process. However, as a rapidlygrowing body of evidence continues to suggest, hardly anything could be further from the truth ( [link] ). The question of worker safety and chemical contamination at chip-making plants has received anincreasing amount of attention over the course of the past decade.

Chemicals used in the manufacturing of semiconductors are known to have toxic effects (image fromFARSHA).

The devices being built at semiconductor fabrication facilities are super-sensitive to environmental contaminants.Because each chip takes dozens of trained personnel several weeks to complete, an enormous amount of time and effort is expended toproduce a single wafer. The industry may pride itself on its perfectly immaculate laboratories and its bunny-suited workers, butit should be noted that the bunny suits are not designed to protect their wearers from hazardous materials but rather to protect theactual semiconductor products from coming into contact with dirt, hair, flakes of skin, and other contaminants that can be shed fromhuman bodies. They protect the silicon wafers from the people, not the people from the chemicals.

Lee Neal, the head of safety, health, and environmental affairs for the Semiconductor Industry Association,has been quoted as saying, “This is an environment that is cleaner than an operating room at a hospital.” However, this boast iscurrently being challenged by industry workers, government scientists, and occupational-health experts across the country andworldwide.

Industrial hygiene has always been an issue in the semiconductor industry. Many of the chemicals involved inthe manufacturing process of semiconductors are known human carcinogens or pose some other serious health risk if not containedproperly. [link] lists ten of the hazardous chemicals most commonly used in manufacturing semiconductors along with theirknown effects on human health.

Chemicals of concern in the semiconductor industry [5].
Chemical name Role in manufacturing process Health problems linked to exposure
Acetone Chemical-mechanical polishing of silicon wafers Nose, throat, lung, and eye irritation, damage to the skin, confusion, unconsciousness, possible coma
Arsenic Increases conductivity of semiconductor material Nausea, delirium, vomiting, dyspepsia, diarrhea, decrease in erythrocyte and leukocyte production, abnormal heart rhythm, bloodvessel damage, extensive tissue damage to nerves, stomach, intestine, and skin, known human carcinogen for lung cancer
Arsine Chemical vapor deposition Headache, malaise, weakness, vertigo, dyspnea, nausea, abdominal and back pain, jaundice, peripheral neuropathy,anemia
Benzene Photoelectrochemical etching Damage to bone marrow, anemia, excessive bleeding, immune system effects, increased chance of infection, reproductiveeffects, known human carcinogen for leukemia
Cadmium Creates “holes” in silicon lattice to create effect of positive charge Damage to lungs, renal dysfunction, immediate hepatic injury, bone defects, hypertension, reproductive toxicity,teratogenicity, known human carcinogen for lung and prostate cancer
Hydrochloric acid Photoelectrochemical etching Highly corrosive, severe eye and skin burns, conjunctivitis, dermatitis, respiratory irritation
Lead Electroplated soldering Damage to renal, reproductive, and immune systems, spontaneous abortion, premature birth, low birth weight, learningdeficits in children, anemia, memory effects, dementia, decreased reaction time, decreased mental ability
Methyl chloroform Washing Headache, central nervous system depression, poor equilibrium, eye, nose, throat, and skin irritation, cardiacarrhythmia
Toluene Chemical vapor deposition Weakness, confusion, memory loss, nausea, permanent damage to brain, speech, vision, and hearing problems, loss of musclecontrol, poor balance, neurological problems and retardation of growth in children, suspected human carcinogen for lung and livercancer
Trichloroethylene Washing Irritation of skin, eyes, and respiratory tract, dizziness, drowsiness, speech and hearing impairment, kidney disease, blooddisorders, stroke, diabetes, suspected human carcinogen for renal cancer

Questions & Answers

how does Neisseria cause meningitis
Nyibol Reply
what is microbiologist
Muhammad Reply
what is errata
Muhammad
is the branch of biology that deals with the study of microorganisms.
Ntefuni Reply
What is microbiology
Mercy Reply
studies of microbes
Louisiaste
when we takee the specimen which lumbar,spin,
Ziyad Reply
How bacteria create energy to survive?
Muhamad Reply
Bacteria doesn't produce energy they are dependent upon their substrate in case of lack of nutrients they are able to make spores which helps them to sustain in harsh environments
_Adnan
But not all bacteria make spores, l mean Eukaryotic cells have Mitochondria which acts as powerhouse for them, since bacteria don't have it, what is the substitution for it?
Muhamad
they make spores
Louisiaste
what is sporadic nd endemic, epidemic
Aminu Reply
the significance of food webs for disease transmission
Abreham
food webs brings about an infection as an individual depends on number of diseased foods or carriers dully.
Mark
explain assimilatory nitrate reduction
Esinniobiwa Reply
Assimilatory nitrate reduction is a process that occurs in some microorganisms, such as bacteria and archaea, in which nitrate (NO3-) is reduced to nitrite (NO2-), and then further reduced to ammonia (NH3).
Elkana
This process is called assimilatory nitrate reduction because the nitrogen that is produced is incorporated in the cells of microorganisms where it can be used in the synthesis of amino acids and other nitrogen products
Elkana
Examples of thermophilic organisms
Shu Reply
Give Examples of thermophilic organisms
Shu
advantages of normal Flora to the host
Micheal Reply
Prevent foreign microbes to the host
Abubakar
they provide healthier benefits to their hosts
ayesha
They are friends to host only when Host immune system is strong and become enemies when the host immune system is weakened . very bad relationship!
Mark
what is cell
faisal Reply
cell is the smallest unit of life
Fauziya
cell is the smallest unit of life
Akanni
ok
Innocent
cell is the structural and functional unit of life
Hasan
is the fundamental units of Life
Musa
what are emergency diseases
Micheal Reply
There are nothing like emergency disease but there are some common medical emergency which can occur simultaneously like Bleeding,heart attack,Breathing difficulties,severe pain heart stock.Hope you will get my point .Have a nice day ❣️
_Adnan
define infection ,prevention and control
Innocent
I think infection prevention and control is the avoidance of all things we do that gives out break of infections and promotion of health practices that promote life
Lubega
Heyy Lubega hussein where are u from?
_Adnan
en français
Adama
which site have a normal flora
ESTHER Reply
Many sites of the body have it Skin Nasal cavity Oral cavity Gastro intestinal tract
Safaa
skin
Asiina
skin,Oral,Nasal,GIt
Sadik
How can Commensal can Bacteria change into pathogen?
Sadik
How can Commensal Bacteria change into pathogen?
Sadik
all
Tesfaye
by fussion
Asiina
what are the advantages of normal Flora to the host
Micheal
what are the ways of control and prevention of nosocomial infection in the hospital
Micheal
what is inflammation
Shelly Reply
part of a tissue or an organ being wounded or bruised.
Wilfred
what term is used to name and classify microorganisms?
Micheal Reply
Binomial nomenclature
adeolu
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Source:  OpenStax, Nanotechnology: content and context. OpenStax CNX. May 09, 2007 Download for free at http://cnx.org/content/col10418/1.1
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