JP-2026075303-A - Method for manufacturing ground stacked wafers, method for manufacturing ground wafers, and method for manufacturing chips

JP2026075303AJP 2026075303 AJP2026075303 AJP 2026075303AJP-2026075303-A

Abstract

[Problem] To provide a method for manufacturing a ground laminated wafer, a method for manufacturing a ground wafer, and a method for manufacturing a chip that can reduce the non-uniformity of the thickness distribution that occurs in the wafer due to grinding. [Solution] The present invention relates to a method for manufacturing a ground laminated wafer, in which a wafer and a support member are laminated with an adhesive layer in between, and involves grinding the wafer of the laminated wafer. The method comprises: a thickness measurement step in which measurement data is obtained regarding the distribution in the direction along the contact surface between adjacent layers with respect to at least one of the total thickness of the laminated wafer, the thickness of the wafer, the thickness of the adhesive layer, or the thickness of the support member; a cutting step in which the support member is cut based on the measurement data obtained in the thickness measurement step so that the thickness distribution of the portion of the laminated wafer excluding the wafer becomes more uniform; and a grinding step in which the wafer is ground after the cutting step. [Selection Diagram] Figure 2

Inventors

山本敬祐

Assignees

株式会社ディスコ

Dates

Publication Date: 20260508
Application Date: 20241022

Claims (6)

A method for manufacturing a ground laminated wafer, comprising grinding a laminated wafer in which a wafer and a support member are laminated with an adhesive layer in between, A thickness measurement step to obtain measurement data relating to the distribution in the direction along the contact surface between adjacent layers with respect to at least one of the total thickness of the stacked wafer, the thickness of the wafer, the thickness of the adhesive layer, or the thickness of the support member, A cutting step in which the support member is cut based on the measurement data obtained in the thickness measurement step so that the thickness distribution of the portion of the stacked wafer excluding the wafer becomes more uniform, A method for manufacturing a ground laminated wafer, comprising: a grinding step of grinding the wafer after the cutting step.
In the cutting step, The stacked wafer is held in a holding mechanism having a holding surface for holding the stacked wafer, A method for manufacturing a ground laminated wafer according to claim 1, wherein a cutting blade attached to the tip of a spindle rotates and contacts the support member of the laminated wafer, and the holding mechanism rotates together with the laminated wafer, thereby cutting the support member.
In the cutting step, A method for manufacturing a ground laminated wafer according to claim 2, wherein the cutting blade is driven into the support member while the holding mechanism is rotated together with the laminated wafer, and the distance between the holding surface of the holding mechanism and the cutting blade is changed according to the position of the cutting blade relative to the holding mechanism.
The support member is, It includes a plate-shaped main material and a resin sheet laminated on one side of the main material, In the laminated wafer, the wafer and the other side of the main material of the support member are bonded together by the adhesive layer. A method for manufacturing a ground laminated wafer according to any one of claims 1 to 3, wherein in the cutting step, the resin sheet of the support member is cut.
After performing the manufacturing method for a ground laminated wafer according to any one of claims 1 to 3, A method for manufacturing a ground wafer, comprising performing a peeling step of peeling the wafer from the ground stacked wafer as a ground wafer.
After performing the manufacturing method for a ground laminated wafer according to any one of claims 1 to 3, A method for manufacturing chips, comprising performing a splitting step of dividing the wafer into chips.

Description

This invention relates to a method for manufacturing a ground laminated wafer, which is formed by grinding a laminated wafer in which a wafer and a support member are laminated with an adhesive layer in between, and also to a method for manufacturing a ground laminated wafer and a method for manufacturing a chip using the same. Device chips used in electronic devices such as mobile phones and personal computers are manufactured by processing semiconductor wafers. On one side of a disc-shaped semiconductor wafer, multiple division lines (streets) are arranged in a grid pattern. Devices such as ICs (Integrated Circuits) and LSIs (Large Scale Integrations) are formed in each rectangular region demarcated by these division lines. By cutting the semiconductor wafer along each division line, the wafer is divided into multiple device chips. In recent years, in the manufacturing of such device chips, wafer thinning has been employed to reduce the size and weight of the chips. For example, in the manufacturing process of the device chips described above, the entire wafer is thinned by grinding the back surface of the wafer on which the device has been formed. In wafer manufacturing processes involving such thinning, a laminated wafer is sometimes used in which another wafer is bonded to the wafer to be processed as a support substrate (support member) to maintain strength even after the wafer has been thinned. By grinding the wafer bonded to the support substrate, sufficient thickness is maintained for the overall strength of the laminated wafer, even as the wafer is thinned (see, for example, Patent Document 1). For bonding wafers to a support substrate in a stacked wafer, an adhesive is used, for example. During bonding, for instance, adhesive is placed on one side of the support substrate, and the substrate is rotated. Centrifugal force spreads the adhesive onto that side, forming a thin film of adhesive (spin coating). The wafer is then placed on this film, bonding the wafer and support substrate via the adhesive layer. Incidentally, while spin coating allows for the easy formation of a thin liquid film on the surface of the object being processed (in this case, the support substrate), it can sometimes result in uneven thickness distribution of the thin film. Especially when using highly viscous liquids such as adhesives, a shape called an edge bead forms on the outer periphery (the outermost part of the area where the thin film is formed, relative to the radial direction of rotation). This can cause, for example, the outermost edge of the thin film to be thicker, while the area immediately inside it becomes thinner. Of course, non-uniformity in the thickness of the thin film (adhesive layer) can occur due to various factors other than edge beads. Furthermore, while the adhesive layer can be formed not only by spin coating, but also, for example, by pressing the wafer and support substrate together with the adhesive sandwiched between them, non-uniformity in the adhesive layer thickness can also occur in such bonding methods due to various factors. If the thickness of the adhesive layer is not uniform, this uneven distribution of thickness can affect the wafer thickness during subsequent grinding. For example, if the wafers and support substrates forming a stacked wafer are uniform in thickness, but the adhesive layer between them is not, grinding the wafer to achieve a uniform total thickness (the overall thickness of the stacked wafer consisting of the wafer, adhesive layer, and support substrate) will result in uneven thickness distribution in the resulting wafer after grinding, corresponding to the thickness of the adhesive layer. Similar problems can occur, for example, when the thickness of the support substrate is uneven. Japanese Patent Publication No. 2013-187281 Figure 1 is a perspective view showing an example of the configuration of a stacked wafer.Figure 2 is a flowchart illustrating a typical procedure for grinding the stacked wafer shown in Figure 1, as a reference example.Figure 3 is a side view showing an example of the grinding process of a stacked wafer.Figure 4(A) is a schematic cross-sectional view showing an example of the state of a stacked wafer before grinding. Figure 4(B) is a schematic cross-sectional view showing an example of the state of a stacked wafer after grinding.Figure 5(A) is a schematic cross-sectional view showing another example of the state of a stacked wafer before grinding. Figure 5(B) is a schematic cross-sectional view showing another example of the state of a stacked wafer after grinding.Figure 6(A) is a schematic cross-sectional view showing yet another example of the state of a stacked wafer before grinding. Figure 6(B) is a schematic cross-sectional view showing yet another example of the state of a stacked wafer after grinding.Figure 7(A) is a schematic cross-sectional view showing yet another example of the state of a stacked wafer before grinding. Figure 7(B) i