Wafer and film coating method of using the same
View Patent ↗The present disclosure provides a wafer that can be used in coating films. The wafer includes a front surface, a back surface opposite to the front surface, and a plurality of trenches. The back surface further includes a central region and a surrounding region. The trenches are disposed on the back surface. The spacing between any two adjacent trenches in surrounding region is less than the spacing between any two adjacent trenches in the central region.
1. A first wafer, utilized in vapor deposition process for depositing films on a second wafer having an active side, comprising:
a right side;
a back side corresponding to the right side and face to the active side of the second wafer, comprising a central region and a surrounding region around the central region; and
a plurality of trenches existing on the back side, wherein the spacing between any two of the adjacent trenches inside the surrounding region is smaller than the spacing between any two of the adjacent trenches insides the central region, configured to increase the reaction area for a reaction gas in the surrounding region, whereby the thickness of each film on the active side of the second wafer corresponding to the surrounding region of the back side is decreased.
2. The first wafer of claim 1 , wherein the trenches are the circular trenches.
3. The first wafer of claim 1 , wherein the average distributed density of the trenches is increased from the central region to the surrounding region.
4. The first wafer of claim 1 , wherein the depth of the trenches are increased from the central region to the surrounding region.
5. The first wafer of claim 1 , wherein the depth of the trenches are the same.
6. A first wafer, utilized in vapor deposition process for depositing films on a silicon wafer having an active side, comprising:
a right side;
a back side corresponding to the right side and face to the active side of the silicon wafer, comprising a central region and a surrounding region around the central region; and
a plurality of trenches existing on the back side, wherein the average distributed density of the trenches in the surrounding region is greater than the average distributed density of the trenches in the central region, configured to increase the reaction area for a reaction gas in the surrounding region, whereby the thickness of each film on the active side of the silicon wafer corresponding to the surrounding region of the back side is decreased.
7. The first wafer of claim 6 , wherein the trenches are the circular trenches.
8. The first wafer of claim 7 , wherein the spacing between any two adjacent trenches inside the surrounding region is smaller than the spacing between any two adjacent trenches insides the central region.
9. The first wafer of claim 6 , wherein the average density of the trenches is increased from the central region to the surrounding region.
10. The first wafer of claim 6 , wherein the depth of the trenches are increased from the central region to the surrounding region.
11. The first wafer of claim 6 , wherein the depth of the trenches are the same.
12. A wafer coating method, comprising:
providing a reactor, the reactor comprising an inlet and an outlet;
placing at least a first wafer and a plurality of second wafers into the reactor, the first wafer and the second wafer are arranged along the first axial,
wherein the first wafer comprises a first right side, a first back side corresponding to the first right side and a plurality of trenches, the first back side comprises a central region and a surrounding region, and the trenches are on the first back side,
wherein each of the second wafers comprises a second right side and a second back side corresponding to the second right side, and the second right side face to the first back side,
wherein the spacing between two adjacent trenches inside the surrounding region is smaller than the spacing between two adjacent trenches inside the central region; and
introducing a reacting gas from the inlet to the reactor, wherein the first wafer is configured to increase the reaction area for the reaction gas in the surrounding region, whereby the thickness of a film formed on the second right side of the second wafer is decreased.
13. The wafer coating method of claim 12 , wherein the first wafer is deposing between two adjacent second wafers.
14. The wafer coating method of claim 12 , wherein the trenches are circular trenches.
15. The wafer coating method of claim 12 , wherein the average distributed density of the trenches in the surrounding region is greater than the average distributed density of the trenches in the central region.
16. The wafer coating method of claim 12 , wherein the depth of the trenches are increased from the central region to the surrounding region.
17. The wafer coating method of claim 12 , wherein the depth of the trenches are the same.
18. The wafer coating method of claim 12 , wherein the average distributed density of the trenches is increased from the central region to the surrounding region.