Specific Process Knowledge/Back-end processing/Laser Micromachining Tool/fluence: Difference between revisions

Latest revision as of 18:04, 27 May 2025

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Fluence definition

The fluence produces by a laser is, by definition, the energy delivered by a laser pulse ( $E_{p u l s e}$ ) per surface unit ( $A$ ) and it is given in J/cm2.

The function $E_{p u l s e}$ is defined as:

E_{p u l s e} = \frac{\overline{P}}{f}

Where $\overline{P}$ (average power) is measured with the laser sensor power measurement (see manual,section 5.3) and the repetion rate ( $f$ ) is set in the parameter file under " laser frequency".

The fluence is therefore determinated as such:

F l u e n c e = \frac{E_{p u l s e}}{A}

The area ( $A$ ) can be determinate with the theoretical min spot diameter (1/e2), available here

Fluence results measurement

The results below have been calculated with the theoretical spot size provided by 3D Micromac.

Fluence result for IR wavelength (1064nm, F255mm)	Fluence result for green wavelength (532nm, F255mm)	Fluence result for UV wavelength (355nm, F103mm)

Fluence result for UV wavelength (355nm, F255mm)	Fluence result for IR wavelength (IPG 1064nm, F255mm). The fluence at 100% and 10kHz must be expected around 25J/cm2

@@ Line 1: / Line 1: @@
+{{cc-nanolab}}
 == Fluence definition ==
-The fluence produces by a laser is, by definition, the energy delivered by a laser pulse (<math>E_{pulse}</math>) per surface unit (<math>S</math>) and it is given in J/cm2.
+The fluence produces by a laser is, by definition, the energy delivered by a laser pulse (<math>E_{pulse}</math>) per surface unit (<math>A</math>) and it is given in J/cm2.
-The function <math>E_{pulse}</math> is defined as :
+The function <math>E_{pulse}</math> is defined as:
@@ Line 11: / Line 14: @@
 Where <math>\overline{P}</math> (average power) is measured with the laser sensor power measurement (see [http://labmanager.danchip.dtu.dk/d4Show.php?id=2885&mach=309|laser manual],section 5.3) and the repetion rate (<math>f</math>) is set in the parameter file under " laser frequency".
-The fluence is therefore determinated as such :
+The fluence is therefore determinated as such:
-: <math>Fluence = \frac{E_{pulse}}{S}\,</math>
+: <math>Fluence = \frac{E_{pulse}}{A}\,</math>
-The theoretical spot sizes (<math>S</math>) can be found [[Specific Process Knowledge/Back-end processing/Laser Micromachining Tool/Spot size and optics|here]]
+The area (<math>A</math>) can be determinate with the theoretical min spot diameter (1/e2), available [[Specific Process Knowledge/Back-end processing/Laser Micromachining Tool/Spot size and optics|here]]
 == Fluence results measurement==
+The results below have been calculated with the theoretical [[Specific Process Knowledge/Back-end processing/Laser Micromachining Tool/Spot size and optics|spot size]] provided by 3D Micromac.
+{| border="1" cellspacing="2" cellpadding="2"
+![[image:161214_FluenceVSrepRate_1064nm_255mm.jpg|500x500px|thumb|center|Fluence result for IR wavelength (1064nm, F255mm)]]
+![[image:161214_FluenceVSrepRate_532nm_255mm.jpg|500x500px|thumb|center|Fluence result for green wavelength (532nm, F255mm)]]
+![[image:161214_FluenceVSrepRate_355nm_103mm.jpg|500x500px|thumb|center|Fluence result for UV wavelength (355nm, F103mm)]]
+|}
 {| border="1" cellspacing="2" cellpadding="2"
-![[image:140414_FluenceVSrepRate_1064nm_255mm_v3.jpg|500x500px|thumb|center|Fluence result for IR wavelength (1064nm, F255mm)]]
+![[image:060815_FluenceVSrepRate_355nm_255mm.jpg|500x500px|thumb|center|Fluence result for UV wavelength (355nm, F255mm)]]
-![[image:140414_FluenceVSrepRate_532nm_255mm_v3.jpg|500x500px|thumb|center|Fluence result for green wavelength (532nm, F255mm)]]
+![[image:140618_FluenceVSrepRate_1064nm_IPG.jpg|500x500px|thumb|center|Fluence result for IR wavelength (IPG 1064nm, F255mm). The fluence at 100% and 10kHz must be expected around 25J/cm2]]
-![[image:140526_FluenceVSrepRate_355nm_255mm_v5.jpg|500x500px|thumb|center|Fluence result for UV wavelength (532nm, F255mm)]]
 |}