| Identification | Back Directory | [Name]
Silicon tetrahydride | [CAS]
7803-62-5 | [Synonyms]
SiH4
SILANE
Silicane
Monosilane
flots100sco
tetrahydrure
Silicomethane
methylsilicane
Silicon hydride
Silaneinnitrogen
15-17% IN NITROGEN
Tetrahydridesilicon
Silicon tetyahydride
SILICON TETRAHYDRIDE
Silane coupler RB-602
Silane coupler RB-902
Silicon hydride (SiH4)
tetrahydruredesilicium
silane,7.0-7.5% in argon
SILANE: 15-17% IN NITROGEN
Silicon tetrahydride (Silane)
SILANE, 7.0 - 7.5% in nitrogen
SilaneGAS(Silicontetrahydride)
SILANE, 99.998+%, ELECTRONIC GRADE | [EINECS(EC#)]
232-263-4 | [Molecular Formula]
H4Si | [MDL Number]
MFCD00011228 | [MOL File]
7803-62-5.mol | [Molecular Weight]
32.12 |
| Chemical Properties | Back Directory | [Appearance]
Silane is a colorless, pyrophoric gas with a repulsive odor. | [Melting point ]
-185 °C | [Boiling point ]
-112 °C | [density ]
1.114 g/mL at 25 °C(lit.)
| [vapor density ]
1.1 (vs air)
| [vapor pressure ]
100kPa at 20℃ | [solubility ]
reacts with H2O; insoluble in ethanol,benzene | [form ]
colorless gas | [color ]
colorless gas; flammable | [Specific Gravity]
0.680 | [Odor]
repulsive odor | [Water Solubility ]
decomposed by H2O; insoluble alcohol, benzene [HAW93] | [Hydrolytic Sensitivity]
10: reacts extremely rapidly with moisture and oxygen - may be pyrophoric - sealed system required | [Merck ]
13,8562 | [Exposure limits]
TLV-TWA 5 ppm (6.5 mg/m3) (ACGIH). | [Contact allergens]
Various silane derivatives are used as bonding agents between glass and the resin used as a coating agent of glass filaments. Organosilanes have been implicated as sensitizers in workers at a glass filament manufactory. | [EPA Substance Registry System]
Silane (7803-62-5) |
| Hazard Information | Back Directory | [Chemical Properties]
Silane is a colorless, pyrophoric gas with a repulsive odor. | [Definition]
ChEBI: The simplest silane, consisting of a single silicon atom carrying four hydrogens. | [Uses]
Source of hyperpure silicon for semiconductors. | [General Description]
Silicon tetrahydride is a colorless, flammable and poisonous gas, with a strong repulsive odor. Silicon tetrahydride is easily ignited in air, reacts with oxidizing agents, is very toxic by inhalation, and is a strong irritant to skin, eyes and mucous membranes. Silicon tetrahydride is lighter than air. Under prolonged exposure to fire or heat the containers may rupture violently and rocket. Silicon tetrahydride is used in the production of amorphous silicon. | [Air & Water Reactions]
Highly flammable. Pure state ignites in air, the first seven to eight of the series 6H2n+1 ignite spontaneously in air at room temperature or slightly elevated temperatures [Mellor 1:376 1946-47]. Slowly reacts with water to form silicon hydroxides and hydrogen gas. | [Reactivity Profile]
Slowly reacts with water to form silicon hydroxides and hydrogen gas [Hydrides of the Elements of Main Groups I IV 1971 p.513]. Silicon tetrahydride burns in contact with bromine, chlorine or covalent chlorides (carbonyl chloride, antimony pentachloride, tin(IV) chloride). Even traces of the free halogens may cause violent explosions, when handling Silicon tetrahydride, extreme caution should be taken, [Mellor, 1940, Vol. 6, 220]. Mixtures of Silicon tetrahydride and nitrogen oxides, nitrous oxide, detonate very easily, [Chem. Abs., 1990, 112, 121711]. | [Health Hazard]
Vapors may cause dizziness or asphyxiation without warning. Some may be toxic if inhaled at high concentrations. Contact with gas or liquefied gas may cause burns, severe injury and/or frostbite. Fire may produce irritating and/or toxic gases. | [Fire Hazard]
EXTREMELY FLAMMABLE. Will be easily ignited by heat, sparks or flames. Will form explosive mixtures with air. Silicon tetrahydride will ignite spontaneously in air. Vapors from liquefied gas are initially heavier than air and spread along ground. Vapors may travel to source of ignition and flash back. Cylinders exposed to fire may vent and release flammable gas through pressure relief devices. Containers may explode when heated. Ruptured cylinders may rocket. | [Hazard]
Dangerous fire risk, ignites spontaneously
in air. Strong irritant to tissue, skin and upper res-
piratory tract.
| [Potential Exposure]
Silane is used as a doping agent for solid-state devices; as a source of silicon for semiconductors; and in the production of amorphous silicon. | [First aid]
If this chemical gets into the eyes, remove any contact lenses at once and irrigate immediately for at least 15 minutes, occasionally lifting upper and lower lids. Seek medical attention immediately. If this chemical contacts the skin, remove contaminated clothing and wash immediately with soap and water. Seek medical attention immediately. If this chemical has been inhaled, remove from exposure, begin rescue breathing (using universal precautions, including resuscitation mask) if breathing has stopped and CPR if heart action has stopped. Transfer promptly to a medical facility. When this chemical has been swallowed, get medical attention. Give large quantities of water and induce vomiting. Do not make an unconscious person vomit. If frostbite has occurred, seek medical attention immediately; do NOT rub the affected areas or flush them with water. In order to prevent further tissue damage, do NOT attempt to remove frozen clothing from frostbitten areas. If frostbite has NOT occurred, immediately and thoroughly wash contaminated skin with soap and water. | [Shipping]
UN2203 Silane, Hazard Class: 2.1; Labels: 2.1-Flammable gas. Cylinders must be transported in a secure upright position, in a well-ventilated truck. Protect cylinder and labels from physical damage. The owner of the compressed gas cylinder is the only entity allowed by federal law (49CFR) to transport and refill them. It is a violation of transportation regulations to refill compressed gas cylinders without the express written permission of the owner. | [Incompatibilities]
An extremely flammable gas. Forms explosive mixture with air; may spontaneously ignite in air. A strong reducing agent. Reacts slowly with water forming silicon hydroxides and flammable hydrogen gas. Reacts with oxidizing agents; halogens , potassium hydroxide solution. Explodes in oxygen. Decomposes on heating or on burning producing silicon and hydrogen. | [Description]
Silane is a colorless, spontaneously flammable (pyrophoric) gas. It has a choking odor and
may form explosive mixtures with air. Silane
will react violently with heavy metal halides and
free halogens other than hydrogen chloride. | [Waste Disposal]
Return refillable compressed gas cylinders to supplier. Dispose by controlled burning or seal cylinders and return to suppliers. | [Flammability and Explosibility]
Pyrophoric | [Materials Uses]
Piping and equipment for silane service may be
of steel or stainless steel construction. Piping
and equipment must be designed to withstand
the pressures involved. Extreme care must be
taken to avoid the contact ofsilane with materials containing heavy-metal halides or free halogens. Silane will react violently or explosively
with these compounds.
Silane systems should be purged of air to prevent silane ignition and contamination with silicon dioxide.
All systems to handle silane should be designed with the following factors in mind:
? Prevention of leakage, both in and out, under vacuum and pressure
? Minimum necessary internal volume
? Elimination of dead spaces
? Isolation ofsystem components in case of
a leak, rupture, or other failure
? Ability to easily evacuate and purge the
system and components with inert gas
? That silane should never be purged
through a vacuum pump
? The use offittings preferably ofthe
welded face seal gasketed type to minimize the likelihood ofleaks
? Use of diaphragm packless valves with resilient seats such as Kel-F
? The removal of backplates from gauges
and rotometers where gases may collect
upon leakage to allow pressure venting away from personnel if an explosion takes
place
? The use ofmetal diaphragm regulators to minimize air diffusion leakage
Consideration ofthe use offlow restrictions in cylinder valves. | [Physiological effects]
The major hazards ofsilane stem from its ability
to combust spontaneously and its irritating
properties. Silane reacts with water to form silicic acid and therefore can cause irritation ofthe
eyes, mucous membranes, and respiratory tract.
Inhalation may result in headache, nausea, and
irritation of the upper respiratory tract. The offensive odors of silane should be taken as a warning signal for the presence of dangerous
concentrations.
ACGIH recommends a Threshold Limit
Value-Time-Weighted Average (TLV-TWA)
of 5 ppm (6.6 mg/m3) for silane. The TLV-TWA is the time-weighted average concentration for a normal 8-hour workday and a 40-hour
workweek, to which nearly all workers may be
repeatedly exposed, day after day, without adverse effect. | [Environmental Fate]
Silane is a colorless transparent gas, heavier than air. It is
odorless when greatly diluted, but extremely noxious when
concentrated, with a sharp, repulsive smell, somewhat similar
to that of acetic acid. Its silicon–hydrogen bond is much
weaker, and accordingly more reactive, than a carbon–
hydrogen single bond. It is not only inflammable in air at
concentrations between 1% and 96% v/v, producing particulate
silicon oxides and hydrogen gas, but is pyrophoric. Above
420°C silane decomposes, releasing hydrogen and depositing
high-purity silicon, which leads to some of its principal
applications. It also reacts avidly with oxidants; for example,
contact with even trace amounts of free halogens may cause
violent explosions. It is insoluble in water, and does not react
with water under normal conditions, but in the presence of
even minute traces of hydroxyl ion reacts to evolve hydrogen
gas and form corrosive silicic acid or hydrated silicon dioxide.
The reaction with water is further accelerated by organic or
inorganic bases. Silane is fully biodegradable, and will not
bioaccumulate. | [storage]
With the proper precautions, silane and silane
mixtures can be handled safely to avoid contact
with air at all times. Almost all recommendations are directed at not violating this one rule.
Specific precautions that should be observed in
handling silane are as follows:
? Before using silane, read all equipment instructions, cylinder labels, data sheets, and
other associated information pertaining to
silane and its use.
? Handle silane in a well-ventilated area
while avoiding the presence of combustible materials.
? Store silane at positive pressures.
? Do not condense silane by avoiding temperatures of-148°F (-100°C) or less.
Condensation ofsilane runs the risk of
leaks developing with subsequent sucking
back of air into the system, forming explosive mixtures.
? Do not use silane in conjunction with
heavy-metal halides or free halogens, with
which it will react violently. Care should
be taken that all components of any
silane-handling system are purged offree
halogens, which might exist from degreasing agents or chlorinated hydrocarbons.
? Evacuate and thoroughly pressure check
all systems, preferably with helium, for
leaks at pressures two to three times the
anticipated working pressure. However, do
not exceed the system design pressure. In
addition, a regular leak test procedure and
testing schedule should be instituted and followed as part of normal preventive
maintenance.
? Ground all equipment and lines using
silane.
? Use an alternate vacuum and inert gas
purge ofthe system to purge all air out of
the system after it has been leak checked
or opened for any reason.
? When pressurizing equipment with silane
or a silane mixture, open the cylinder valve
slowly. All other equipment adjustments of
regulators, needle valves, etc. should also
be made slowly.
? Before disconnecting any system that has
had silane in it, thoroughly purge the system ofsilane with an inert gas. Any portion of a system that is dead-ended or allows "pocketing" ofsilane should be
treated by considerable purging, on the order often times the trapped volume.
? Vent silane or silane mixtures through
small diameter pipe or tubing, ending under a shallow water seal to prevent back
diffusion ofair. Venting should be to an
area designed for silane disposal, preferably by burning. Concentrations even in the
low percentage range are dangerous and
should not be exposed directly to air.
Silane can also be vented by diluting with
inert gas to prevent ignition upon discharge to the atmosphere.
In addition, all precautions necessary for the
safe handling of any toxic flammable gas must
be observed. | [GRADES AVAILABLE]
Silane is usually sold in very high purity grades
primarily for use in the electronics industry. |
| Safety Data | Back Directory | [Hazard Codes ]
F+,Xn | [Risk Statements ]
12-17-20 | [Safety Statements ]
9-16-33-36/37/39 | [RIDADR ]
UN 2203 2.1
| [WGK Germany ]
1
| [RTECS ]
VV1400000
| [TSCA ]
Yes | [DOT Classification]
2.1 (Flammable gas) | [HazardClass ]
2.1 | [Safety Profile]
Mildly toxic by inhalation. Silanes are irritating to skin, eyes, and mucous membranes. Easily ipted in air. Explosive reaction or ignition on contact with halogens or covalent halides (e.g., bromine, chlorine, carbonyl chloride, antimony pentachloride, tin(Iv> chloride). Ignites in oxygen. Can react with oxidizers. It may self-explode. When heated to decomposition it burns or explodes. | [Hazardous Substances Data]
7803-62-5(Hazardous Substances Data) |
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