Micro-miniature gas chromatograph column disposed in silicon wafers

Patent · Sat Jan 01 00:00:00 EST 2000

OSTI ID:873014

Yu, Conrad M ^[1]

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1. Antioch, CA

A micro-miniature gas chromatograph column is fabricated by forming matching halves of a circular cross-section spiral microcapillary in two silicon wafers and then bonding the two wafers together using visual or physical alignment methods. Heating wires are deposited on the outside surfaces of each wafer in a spiral or serpentine pattern large enough in area to cover the whole microcapillary area inside the joined wafers. The visual alignment method includes etching through an alignment window in one wafer and a precision-matching alignment target in the other wafer. The two wafers are then bonded together using the window and target. The physical alignment methods include etching through vertical alignment holes in both wafers and then using pins or posts through corresponding vertical alignment holes to force precision alignment during bonding. The pins or posts may be withdrawn after curing of the bond. Once the wafers are bonded together, a solid phase of very pure silicone is injected in a solution of very pure chloroform into one end of the microcapillary. The chloroform lowers the viscosity of the silicone enough that a high pressure hypodermic needle with a thumbscrew plunger can force the solution into the whole length of the spiral microcapillary. The chloroform is then evaporated out slowly to leave the silicone behind in a deposit.

• Research Organization: Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)
• DOE Contract Number: W-7405-ENG-48
• Assignee: Regents of University of California (Oakland, CA)
• Patent Number(s): US 6068780
• OSTI ID: 873014
• Country of Publication: United States
• Language: English

Related Subjects

micro-miniature
gas
chromatograph
column
disposed
silicon
wafers
fabricated
forming
matching
halves
circular
cross-section
spiral
microcapillary
bonding
visual
physical
alignment
methods
heating
wires
deposited
outside
surfaces
wafer
serpentine
pattern
cover
inside
joined
method
etching
window
precision-matching
target
bonded
vertical
holes
pins
posts
corresponding
force
precision
withdrawn
curing
bond
solid
phase
pure
silicone
injected
solution
chloroform
lowers
viscosity
pressure
hypodermic
needle
thumbscrew
plunger
length
evaporated
slowly
leave
deposit
outside surfaces
outside surface
silicon wafer
solid phase
gas chromatograph
silicon wafers
alignment methods
column disposed
pure silicon
alignment holes
chromatograph column
circular cross-section
micro-miniature gas
heating wire
alignment method
precision alignment
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