Specific Process Knowledge/Thin film deposition/Deposition of Tungsten/Sputtering of W in Sputter Coater 3: Difference between revisions

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 ==X-ray Reflectivity==
-The samples used for X-ray analysis (Instrument: [[Specific Process Knowledge/Characterization/XRD/XRD_SmartLab|XRD SmartLab]]) were prepared in a big glass chamber with 80mA current and a deposition time of 300s.
+The samples used for X-ray analysis (Instrument: [[Specific Process Knowledge/Characterization/XRD/XRD_SmartLab|XRD SmartLab]]) were prepared in a large glass chamber with an 80 mA current and a deposition time of 300 seconds.
-X-ray reflectivity (XRR) profiles for W films at two different positions on the 100mm wafer have been obtained using the Rigaku XRD SmartLab equipment. The voltage and current settings for the Cu X-ray tube were standard  40kV and 30mA. The incident optics contained a IPS (incident parallel slit) adaptor with 5 &deg; Soller slit. Other slits: IS=0.03mm RS1=0.03mm and RS2=0.075mm. Step size: 0.01 and measurement time - 5s for each point. Fitting procesure was performed using the commercial GlobalFit software assuming the model based on a Si substrate with native oxide followed by the deposited W film with thin oxides and moisture surfaces. The results are summarized in a table below.
+X-ray reflectivity (XRR) profiles for W films at two different positions on a 100 mm wafer have been obtained using the Rigaku XRD SmartLab equipment. The voltage and current settings for the Cu X-ray tube were standard: 40 kV and 30 mA. The incident optics contained an IPS (incident parallel slit) adapter with a 5 ° Soller slit. Other slits: IS=0.03mm, RS1=0.03mm, and RS2=0.075mm. Step size: 0.01 and measurement time - 5s for each point. The fitting procedure was performed using the commercial GlobalFit software, assuming a model based on a Si substrate with native oxide, followed by the deposited W film with thin oxides and moisture-sensitive surfaces. The results are summarized in a table below.
@@ Line 90: / Line 90: @@
 |-
-|<b>Moisture/WO<sub>3</sub></b>
+|style="background:WhiteSmoke; color:black"|<b>Moisture/WO<sub>3</sub></b>
-|0.98
+|style="background:WhiteSmoke; color:black"|0.98
-|2.75
+|style="background:WhiteSmoke; color:black"|2.75
-|1.04
+|style="background:WhiteSmoke; color:black"|1.04
 |style="background:WhiteSmoke; color:black"|8.8007e-6
 |style="background:WhiteSmoke; color:black"|2.0437e-7
 |-
-|<b>W</b>
+|style="background:WhiteSmoke; color:black"|<b>W</b>
-|<p style="color:red;"><b>10.14</b></p>
+|style="background:WhiteSmoke; color:black"|<p style="color:red;"><b>10.14</b></p>
-|5.70
+|style="background:WhiteSmoke; color:black"|5.70
-|0.81
+|style="background:WhiteSmoke; color:black"|0.81
 |style="background:WhiteSmoke; color:black"|1.8574e-5
 |style="background:WhiteSmoke; color:black"|4.3131e-7
 |-
-|<b>SiO<sub>2</sub> (native oxide)</b>
+|style="background:WhiteSmoke; color:black"|<b>SiO<sub>2</sub> (native oxide)</b>
-|1.52
+|style="background:WhiteSmoke; color:black"|1.52
-|2.18
+|style="background:WhiteSmoke; color:black"|2.18
-|0.30
+|style="background:WhiteSmoke; color:black"|0.30
 |style="background:WhiteSmoke; color:black"|7.0883e-6
 |style="background:WhiteSmoke; color:black"|9.2376e-8
 |-
-|<b>Si (wafer)</b>
+|style="background:WhiteSmoke; color:black"|<b>Si (wafer)</b>
-|<math>\infty</math>
+|style="background:WhiteSmoke; color:black"|<math>\infty</math>
-|2.328
+|style="background:WhiteSmoke; color:black"|2.328
-|0.00
+|style="background:WhiteSmoke; color:black"|0.00
 |style="background:WhiteSmoke; color:black"|7.5795e-6
 |style="background:WhiteSmoke; color:black"|1.7601e-7
@@ Line 135: / Line 135: @@
 |-
-|<b>Moisture/WO<sub>3</sub></b>
+|style="background:WhiteSmoke; color:black"|<b>Moisture/WO<sub>3</sub></b>
-|2.22
+|style="background:WhiteSmoke; color:black"|2.22
-|2.63
+|style="background:WhiteSmoke; color:black"|2.63
-|1.17
+|style="background:WhiteSmoke; color:black"|1.17
 |style="background:WhiteSmoke; color:black"|8.5746e-6
 |style="background:WhiteSmoke; color:black"|1.9912e-7
 |-
-|<b>W</b>
+|style="background:WhiteSmoke; color:black"|<b>W</b>
-|<p style="color:red;"><b>6.53</b></p>
+|style="background:WhiteSmoke; color:black"|<p style="color:red;"><b>6.53</b></p>
-|8.10
+|style="background:WhiteSmoke; color:black"|8.10
-|0.81
+|style="background:WhiteSmoke; color:black"|0.81
 |style="background:WhiteSmoke; color:black"|2.6387e-5
 |style="background:WhiteSmoke; color:black"|6.1274e-7
 |-
-|<b>SiO<sub>2</sub> (native oxide)</b>
+|style="background:WhiteSmoke; color:black"|<b>SiO<sub>2</sub> (native oxide)</b>
-|2.23
+|style="background:WhiteSmoke; color:black"|2.23
-|2.12
+|style="background:WhiteSmoke; color:black"|2.12
-|0.37
+|style="background:WhiteSmoke; color:black"|0.37
 |style="background:WhiteSmoke; color:black"|6.8799e-6
 |style="background:WhiteSmoke; color:black"|8.9659e-8
 |-
-|<b>Si (wafer)</b>
+|style="background:WhiteSmoke; color:black"|<b>Si (wafer)</b>
-|<math>\infty</math>
+|style="background:WhiteSmoke; color:black"|<math>\infty</math>
-|2.328
+|style="background:WhiteSmoke; color:black"|2.328
-|0.00
+|style="background:WhiteSmoke; color:black"|0.00
 |style="background:WhiteSmoke; color:black"|7.5795e-6
 |style="background:WhiteSmoke; color:black"|1.7601e-7
@@ Line 174: / Line 174: @@
-<gallery caption="Big glass chamber. 100mm wafer loaded. X-ray analysis." widths="450px" heights="400px" perrow="3">
+<gallery caption="Big glass chamber. 100mm wafer loaded. X-ray analysis." widths="270px" heights="250px" perrow="3">
 image:eves_W_sputter_coater_3_big_glass_flat_80mA_300s_s1_center_XRR_20220915.png| 300s, 80mA. Center of the wafer.
 image:eves_W_sputter_coater_3_big_glass_flat_80mA_300s_s1_edge_XRR_20220915.png| 300s, 80mA. Edge of the wafer.
-image:eves_W_sputter_coater_3_big_glass_uniformity_20220916.png| Uniformity of W thickness across a 100 mm  wafer in the big glass configuration.
+image:eves_W_sputter_coater_3_big_glass_uniformity_20220916.png| Uniformity of W thickness across a 100 mm wafer in the big glass configuration.
 </gallery>
-The fitted value of the tungsten density (5-8 g/cm<sup>3</sup>) is much less than the bulk value of pure W which is 19.25 g/cm<sup>3</sup>. This low value is very similar to the density of stoichiometric tungsten oxide WO<sub>3</sub> which is 7.16 g/cm<sup>3</sup>. XPS however proves that 67% of the film contains tungsten oxide and 33% W, so this low density can not be explained by the oxidation event only. The most logical explanation is to assume that the layer is not very dense. It contains a lot of nanopores, grain imperfections, etc.
+The fitted value of the tungsten density (5-8 g/cm<sup>3</sup>) is much less than the bulk value of pure W, which is 19.25 g/cm<sup>3</sup>. This low value is very similar to the density of stoichiometric tungsten oxide WO<sub>3</sub>, which is 7.16 g/cm<sup>3</sup>. XPS, however, reveals that 67% of the film consists of tungsten oxide and 33% W, so this low density cannot be explained solely by the oxidation event. The most logical explanation is to assume that the layer is not very dense. It contains numerous nanopores, grain imperfections, and other defects.
 ==Deposition rate and Uniformity==