This article deals with the analysis of small sample volume by using a
planar microcoil and a micromachined cavity. This microcoil is used as a
nuclear magnetic resonance (NMR) radio frequency detection coil in order to
perform in vitro NMR analysis of the sample introduced into the microcavity.
It is a real challenging task to develop microsystem for NMR spectrum
extraction for smaller and smaller sample volume. Moreover, it is
advantageous that these microsystems could be integrated in a Micro Total
Analysing System ($\mu $-TAS) as an analysing tool.
In this paper, NMR theory, description, fabrication process and electrical
characterization of planar microcoils receiver are described. Results
obtained on NMR microspectroscopy experiments have been performed on water
and ethanol, using a 1 mm diameter planar coil. This microcoil is tuned and
matched at 85.13 MHz which is the Larmor frequency of proton in a 2 T
magnetic field.