TWI584075B - Wafer stepping exposure apparatus and method for wafer stepping and exposure - Google Patents

Description

Wafer step exposure device and wafer step exposure method

A wafer exposure apparatus and a wafer exposure method, in particular, a wafer step exposure apparatus and a wafer step exposure method.

With the miniaturization of integrated circuits and the development of three-dimensional structures, micron-level exposure accuracy is required, resulting in very expensive process costs. For example, for exposure of 300 mm or 450 mm wafers, conventional contact printing or proximity printing requires 350 mm or 500 mm reticle, not only cost. Very expensive, and the density of defects in the production process is also quite troublesome.

In addition, the conventional projection wafer stepping exposure device has a reduction lens disposed between the mask and the wafer, and has a depth of focus limitation, and a thick film photoresist cannot be used. . Furthermore, the wafer exposure apparatus has a multi-layer design such as a mercury lamp, a laser light source, a filter, and a condenser lens, which not only has a high cost, but also affects the alignment accuracy due to the process temperature. In view of this, how to reduce the manufacturing cost of the wafer exposure device and maintain good exposure accuracy is the purpose of the development of the case.

One of the objectives of the present invention is to reduce the manufacturing cost of the wafer exposure apparatus and maintain good exposure accuracy. To achieve the above object, the present invention provides a wafer step exposure apparatus. For wafers and reticle, the surface of the wafer has a photoresist layer, and one of the plurality of regions of the wafer has a size similar to that of the reticle. The device includes a wafer carrier, a reticle stage, and a light source. The wafer carrier is configured to fix the wafer; the reticle stage is configured to fix the reticle, and is movable relative to the wafer carrier to align the pattern area of the reticle with one of the regions, wherein The reticle-mounted reticle stage and the wafer-attached wafer-bearing stage are operable to be in direct contact or have only a gap; in addition, the light source provides light for passing through the pattern area of the reticle to the photoresist layer Exposure.

In an embodiment of the invention, the reticle carrier and the wafer carrier can perform relative motion perpendicular to the wafer carrier normal vector, and the relative motion distance is between 0 and 450 mm.

In an embodiment of the invention, the reticle carrier and the wafer carrier can perform relative motion parallel to the wafer carrier normal vector, and the relative motion distance is between 0 and 30 mm.

In one embodiment of the invention, the wafer size is from 1 to 45 times the size of the mask, and the mask size is from 1 to 45 times the pattern area.

In an embodiment of the invention, the pattern line width in the pattern region of the photomask is substantially equal to the pattern line width completed in the wafer after exposure.

To achieve the foregoing objective, the present invention provides a wafer step exposure apparatus for a wafer and a photomask having a photoresist layer on a surface thereof, and a size of one of a plurality of regions of the wafer and a pattern region of the photomask Similarly, the device includes a wafer carrier, a reticle stage, and a light source. The wafer carrier is configured to fix the wafer; the reticle stage is configured to fix the reticle, and is movable relative to the wafer carrier to align the pattern area of the reticle with one of the regions, wherein The reticle is in direct contact with the photoresist layer or has only a gap; in addition, the light source provides light for exposing the photoresist layer through the pattern region of the reticle.

To achieve the foregoing objective, the present invention provides a wafer step exposure method comprising providing a wafer having a plurality of regions and having a photoresist layer on a surface of the wafer; aligning the exposure module to the regions of the wafer In one of the embodiments, the exposure module includes a reticle and a light source, and the reticle pattern The size of the region is similar to one of the regions; the reticle is adjacent to the photoresist layer to leave only a void or in direct contact with the photoresist layer; the light source provides light to pass through the patterned region of the reticle to expose the photoresist layer; The exposure module moves relative to the wafer.

In an embodiment of the present invention, the wafer stepwise exposure method uses a relative motion perpendicular to the wafer normal vector between the exposure module and the wafer, and the relative motion distance is between 0 and 450 mm. After exposing a portion of the photoresist layer of one of the regions, the other portion of the photoresist layer in the regions is exposed.

In an embodiment of the present invention, the wafer stepwise exposure method uses a relative motion parallel to the wafer normal vector between the exposure module and the wafer, and the relative motion distance is between 0 and 30 mm. A portion of the photoresist layer of one of the regions is exposed.

In an embodiment of the invention, the wafer is disposed on a wafer carrier, and the wafer carrier moves to cause relative movement between the exposure module and the wafer.

In an embodiment of the invention, in the above-described wafer stepwise exposure method, the pattern line width completed in the wafer after exposure is substantially equal to the pattern line width in the pattern region of the reticle.

The above and other objects, features and advantages of the present invention will become more <RTIgt;

10‧‧‧ Wafer Carrier

100,200‧‧‧ wafer stepper exposure device

12‧‧‧ wafer

120‧‧‧Multiple areas

121~124‧‧‧Area

13‧‧‧Photoresist layer

20‧‧‧Photomask carrier

25‧‧‧Photomask

251‧‧‧pattern area

30‧‧‧Light source

301‧‧‧Light

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a side elevational view of a first embodiment of a wafer stepper exposure apparatus of the present invention.

2 is a side elevational view of a second embodiment of a wafer stepper exposure apparatus of the present invention.

3 is a schematic view showing the operation of some components of the wafer step exposure apparatus of the present invention.

Please refer to FIG. 1. FIG. 1 is a first embodiment of the wafer stepwise exposure apparatus of the present invention. A side view of the embodiment. The wafer step exposure apparatus 100 of the present embodiment includes a wafer carrier 10, a mask carrier 20, and a light source 30. The wafer carrier 10 is used to fix the wafer 12, and the wafer 12 can be fixed on the wafer carrier 10. The mask carrier 20 is used to fix the mask 25. The mask carrier 20 can clamp the mask 25. Both sides or around the edge of the reticle 25 (as shown in FIG. 3), or other similarly fixed manner, as long as the pattern area 251 of the reticle 25 is not shielded, wherein the reticle 25 can be larger than the size of the pattern area 251. Can be between 1 and 45 times. In addition, the wafer 12 may be 1 to 45 times larger than the mask 25, and the wafer 12 has a photoresist layer 13 on the surface thereof, and the wafer 12 has a plurality of regions 120, and the size of each region may be uniform (see FIG. 3). Shown). The mask carrier 20 is disposed above the wafer carrier 10 such that the mask 25 can face the wafer 12 having the photoresist layer 13.

The wafer carrier 10 and the mask carrier 20 of the embodiment can be moved relative to each other for the relative movement of the wafer 12/wafer carrier 10 and the mask 25, so that the pattern area 251 of the mask 25 can be Aligning one of the regions 120 of the wafer, for example, the pattern region 251 of the reticle 25 is aligned with the region 121 of the wafer 12. Referring to FIG. 3, in the embodiment, the mask carrier 20 and the wafer carrier 10 can perform relative motion parallel to the normal distance of the wafer carrier 10, that is, relative motion along the Z axis, for example, a mask. The carrier 20 is stationary and the wafer carrier 10 is moved upwards, and the relative motion distance can be between 0 and 30 mm. In addition, the mask carrier 20 and the wafer carrier 10 can also perform relative motion perpendicular to the normal distance of the wafer carrier 10, for example, the mask carrier 20 is fixed, and the wafer carrier 10 is along the X-axis or The Y axis is either moved in either direction by the plane formed by the X axis and the Y axis, and the relative motion distance may be between 0 and 450 mm.

It should be noted that the size of the pattern area 251 of the photomask 25 to which the wafer step exposure apparatus 100 is applied is similar to that of each area in the wafer 12, that is, due to the pattern line width in the pattern area 251 of the present embodiment. The line widths of the pattern lines formed in the wafer 12 after exposure are substantially equal (not shown), and the projection lens of the conventional wafer stepper device is not required between the wafer carrier 10 and the mask carrier 20. Therefore, there is only a gap between the reticle stage 20 to which the reticle 25 is fixed and the wafer stage 10 to which the wafer 12 is fixed, in other words, the combination of the reticle 25 and the reticle stage 20 and the wafer 12 and wafer carrier The combination between the stages 10 has only a gap, as shown in Figure 1, the mask 25 There is only a gap between the wafer 12 and the wafer 12. Accordingly, the present embodiment can not only achieve the purpose of saving process cost, but also solve the limitation of depth of field.

In addition, the light source 30 can be disposed above the reticle stage 20 to provide light 301 for exposing the photoresist layer 13 through the pattern region 251 of the reticle 25, for example, a portion of the photoresist of the region 121 of the wafer 12. Layer 13 is exposed to transfer the pattern of mask region 251 to wafer 12 region 121. The light source 30 can include an LED array and a micro lens array (not shown), and the LED array and the microlens array are aligned with each other, thereby replacing the conventional exposure. Mercury lamps or lasers used in the device, as well as multi-layer designs such as filters, condenser lenses, and projection lenses, can avoid thermal expansion of the process and cause errors in multilayer alignment, thereby improving stability and reducing process cost.

In addition, the reticle stage to which the reticle is attached can directly contact the wafer carrier to which the wafer is fixed. In other words, the combination of the reticle and the reticle stage directly contacts the combination of the wafer and the wafer carrier. Referring to FIG. 2, FIG. 2 is a side view showing a second embodiment of a wafer stepwise exposure apparatus of the present invention. For example, in the wafer step exposure apparatus 200 of the second embodiment, the photomask 25 directly contacts the wafer 12, that is, the photomask 25 can directly contact the photoresist layer 13 of the wafer 12; or according to other design changes, the light The cover carrier 20 directly contacts the wafer 10 carrier (not shown). Accordingly, the wafer stepper apparatus 200 can also achieve a reduction in process cost, a resolution of depth of field, and improved device stability.

The present invention further provides an embodiment of a wafer step exposure method. Referring to FIGS. 1 through 3, first, a wafer 12 is provided. The wafer 12 can have a plurality of regions 120 of substantially the same size, and the wafer 12 has a photoresist layer 13 on its surface. Further provided is an exposure module comprising a reticle 25 and a light source 30, wherein the reticle 25 has a pattern area 251, and the size of the pattern area 251 is similar to one of the areas 120. Next, the exposure module is aligned with the surface of the wafer 12 having the photoresist layer 13 and one of the regions 120 of the exposure module is aligned, for example, the pattern region 251 of the mask 25 is aligned with the wafer 12. The area 121 in the area 120. The exposure module may also include a reticle stage 20 for fixing the reticle 25.

In addition, the wafer 12 can be disposed on the wafer carrier 10, and then the relative movement between the exposure module and the wafer 12 can be performed. For example, the exposure module is not moved, and the wafer carrier 10 can be along the wafer 12/. The normal vector of the wafer carrier 10 moves in a vertical direction, such as along the X-axis or the Y-axis or in any direction on the plane formed by the X-axis and the Y-axis, to make the target area of the wafer 12, such as the area 121. Moving from a starting point (not shown) to below the mask area 25 of the mask 25 and aligned therewith. Next, the light source 30 can provide light 301 through the pattern region 251 of the reticle 25 to expose the photoresist layer 13 on the target region 121, and transfer the pattern of the pattern region 251 to the wafer region 121. Thereafter, the wafer carrier 10 can be moved along the X axis, aligning the area 122 or 123 of the wafer 12 with the pattern area 251 and exposing it; or moving along the Y axis, and the area 124 of the wafer 12 and the pattern Zone 251 is aligned and exposed. The relative movement distance between the exposure module and the wafer 12 in either direction of the X-axis or the Y-axis or the plane formed by the X-axis and the Y-axis may be between 0 and 450 mm.

In addition, the relative movement of the exposure module and the wafer 12 in parallel with the normal vector of the wafer 12 can be performed. For example, the exposure module is not moved, and the wafer carrier 10 can be moved along the Z axis. Therefore, the wafer 12 can be along The Z-axis is close to the reticle 25, leaving only a gap between the photoresist layer 13 and the reticle 25 (as shown in FIG. 1) or directly contacting the two (as shown in FIG. 2), and then facing the pattern region 251. A portion of the photoresist layer 13 of one of the regions 120 is exposed. The relative movement distance between the exposure module and the wafer 12 on the Z axis may be between 0 and 30 mm. It should be noted that the relative movement of the exposure module and the wafer 12 in either direction on the Z axis, the X axis, the Y axis, or the plane formed by the X axis and the Y axis is not limited, and may be in accordance with the wafer. The process of the regions 120 of 12 is determined in the order of the processes. Furthermore, in the present invention, the wafer carrier 10 can also be fixed and moved by the exposure module.

Accordingly, in the foregoing relative motion, the exposure module or wafer 12/wafer carrier 10 can be moved from a starting point (not shown) to a three-dimensional coordinate (x, y, z), and x and y Values range from 0 to 450 mm and z values range from 0 to 30 mm.

The light source 30 can include an array of light emitting diodes and an array of microlenses (not shown). Therefore, the array of light emitting diodes can provide light 301 through the array of microlenses and pass through The pattern region 251 of the mask 25 exposes the photoresist layer 13 on one of the regions 120 of the wafer 12, whereby the embodiment replaces the mercury lamp or the laser, and the filter and the collecting lens. Multi-layer design such as projection lens can improve stability and reduce process cost. In addition, the line width of the pattern in the pattern region 251 of the embodiment is substantially equal to the line width of the pattern formed in the wafer 12 after exposure (not shown). Therefore, the wafer 12 and the mask are in this embodiment. The projection lens of the conventional wafer stepper exposure device is not required to be provided in the 25th. According to the embodiment, the embodiment can not only achieve the purpose of saving the process cost, but also solve the limitation of the depth of field.

While the present invention has been described in its preferred embodiments, the present invention is not intended to limit the invention, and the present invention may be modified and modified without departing from the spirit and scope of the invention. The scope of protection is subject to the definition of the scope of the patent application.

10‧‧‧ Wafer Carrier

100‧‧‧Watt stepper exposure device

12‧‧‧ wafer

13‧‧‧Photoresist layer

20‧‧‧Photomask carrier

25‧‧‧Photomask

30‧‧‧Light source

301‧‧‧Light

Claims (11)

A wafer step-exposure device for a wafer and a photomask having a photoresist layer on a surface thereof, and one of a plurality of regions of the wafer has a size similar to a pattern region of the mask The device includes: a wafer carrier for fixing the wafer; a mask carrier for fixing the mask, and a relative movement with the wafer carrier for the mask The pattern area is aligned with one of the areas, wherein the mask carrier and the wafer carrier are operable to be in direct contact or have only one gap; and a light source providing light for passing the light The photoresist layer is directly exposed after the pattern region of the mask. The wafer stepper exposure apparatus of claim 1, wherein the reticle stage and the wafer carrier are movable perpendicular to the wafer carrier normal vector, and the relative motion distance is between 0 to 450 mm. The wafer stepper exposure apparatus of claim 1, wherein the reticle stage and the wafer carrier are movable in parallel with the normal distance of the wafer carrier, and the relative motion distance is between 0 to 30 mm. The wafer stepper exposure apparatus of claim 1, wherein the wafer size is 1 to 45 times the size of the mask, and the mask size is 1 to 45 times the pattern area. The wafer stepper exposure apparatus of claim 1, wherein a pattern line width in the pattern region of the mask is substantially equal to a pattern line width completed in the wafer after exposure. A wafer step exposure method, comprising: providing a wafer having a plurality of regions, the wafer surface having a photoresist layer; and aligning an exposure module to the regions of the wafer In one embodiment, the exposure module includes a reticle and a light source, and a pattern area of the reticle is similar in size to one of the regions; the reticle is adjacent to the photoresist layer to leave only a gap or Directly contacting the photoresist layer; the light source provides light to pass through the pattern region of the mask to directly expose the photoresist layer; and the exposure module moves relative to the wafer. The wafer step exposure method according to claim 6, wherein the relative movement of the exposure module and the wafer is perpendicular to the normal vector of the wafer, and the relative motion distance is 0 to 450 mm. After exposing a portion of the photoresist layer to one of the regions, the other portion of the regions is exposed to the photoresist layer. The wafer step-exposure method of claim 6, wherein the relative movement of the exposure module is parallel to the wafer normal vector, and the relative motion distance is between 0 and 30 mm. A portion of the photoresist layer of one of the regions is exposed. The wafer step exposure method of claim 6, wherein the wafer is disposed on a wafer carrier, and the wafer carrier moves The exposure module and the wafer are moved relative to each other. The wafer step exposure method of claim 6, wherein the pattern line width completed in the wafer after exposure is substantially equal to the pattern line width in the pattern region of the mask. A wafer step-exposure device for a wafer and a photomask having a photoresist layer on a surface thereof, and one of a plurality of regions of the wafer has a size similar to a pattern region of the mask The device includes: a wafer carrier for fixing the wafer; a mask carrier for fixing the mask, and a relative movement with the wafer carrier for the mask The pattern area is aligned with one of the areas, wherein the mask has direct contact with the photoresist layer or has only one gap; and a light source provides light for passing through the pattern area of the mask The photoresist layer is directly exposed.