Olympus BL-AC40TS-C2 사용자 설명서 - 페이지 3
{카테고리_이름} Olympus BL-AC40TS-C2에 대한 사용자 설명서을 온라인으로 검색하거나 PDF를 다운로드하세요. Olympus BL-AC40TS-C2 5 페이지. Micro cantilever
페이지 인쇄4
Tetrahedral tip in two stage structure
The tip profile is symmetric with a half tip angle of 18 degrees macroscopically (see left below).
The side tip profile is asymmetric with a tip angle of 35 degrees. When the cantilever chip is
attached to a chip holder in your AFM with an angle, about 10 degrees, the asymmetry is
improved (see right below).
Scan line profile
Front view
A two stage structure is employed in this probe.
(see left illustration)
The head of the probe tip is made of silicon and
tetrahedral in shape. The foot of the probe tips is
also made of silicon, but covered with a silicon
nitride film.
There is a discontinuity in the probe shape
midway between base and apex. The measurable
sample height therefore limited to the height of
the tip (3.5 micron).
As can be seen in the left illustration,
a tetrahedral tip is located near the triangular end
of the cantilever. When observing the cantilever
from the reflex side, a triangular pocket can be
seen near the free end of the cantilever, marking
the base of the tetrahedral tip. Operators can
therefore easily locate the tip position relative to
samples under optical microscope observation by
finding the center of the triangular pocket. This
makes alignment of the tip with sample very easy
in AFMs, combined with optical microscopes.
Scan line profile
Side view
- 5e -
The apex of the tetrahedral tip becomes sharper due to an oxide sharpening process. The tip
angle in the final few hundred nano meter of the apex, is about 15 to 25 degrees (see below).
When you set your samples to your instrument, please consider the unique shape of the
tetrahedral tip, that is 'good symmetry', when viewing from front side and choose the direction
of the sample. When measuring long grooves, you can get an idea of what angle of the cut will
be quickly by aligning the cantilever along the grooves and scanning across at right angles
against grooves (see below).
5
Trouble-shooting guide
Situations as described below may arise when using this type of cantilever.
Case 1: I tried optimizing imaging parameters first in air before. However good parameter
values cannot be found and the cantilever oscillated.
Solution:
From the beginning, try to optimize the measurement condition in water,
optics, cantilever sensitivity, I-gain, P-gain and frequency tuning.
Selecting a smaller oscillation amplitude of cantilever for AC mode AFM measurement
may gives better images because the tip is sharp and the cantilever is shorter than
conventional cantilevers.
e.g
., sensor
- 6e -