TWI768031B - Method for forming semiconductor device - Google Patents

Abstract

A method for forming a semiconductor device includes providing a substrate, forming a first light-shielding layer on the substrate, performing a first lithography process to pattern the first light-shielding layer to form a plurality of first openings in the first light-shielding layer. The first openings expose pixels of the substrate. The method also includes placing a first stencil on the first light-shielding layer. The first stencil has a first openwork pattern which exposes the pixels of the substrate. The method also includes providing a first material. The first material includes a transparent material. The method also includes applying the first material onto the substrate through the first stencil to cover the pixels and fill the first openings, such that a plurality of first transparent pillars made of the first material are formed on the pixels.

Description

Method of forming semiconductor device

Embodiments of the present invention relate to a method of forming a semiconductor device, and particularly, to a method of forming a semiconductor device including a transparent material and a light-shielding material.

Semiconductor devices can be used in various applications. For example, a semiconductor device may be used as a fingerprint identification device (or at least a part of a fingerprint identification device). Fingerprint recognition devices can be composed of a large number of optical elements. For example, the aforementioned optical elements may include a light collimator, a beam splitter, a focusing mirror, and a linear sensor.

The function of the light collimator is to collimate light to reduce the energy loss caused by light divergence. For example, an optical collimator can be used in a fingerprint identification device to increase the performance of the fingerprint identification device.

However, existing light collimators and methods of forming the same are not satisfactory in all respects.

According to some embodiments of the present invention, a method of forming a semiconductor device is provided. The above method includes providing a substrate. The above-mentioned substrate includes a plurality of pixels. The above-mentioned method also includes forming a first light shielding layer on the above-mentioned substrate, performing a first light The first light shielding layer is patterned by a lithography process to form a plurality of first openings in the first light shielding layer. The plurality of first openings expose a plurality of pixels of the substrate. The above method also includes placing a first template on the first light shielding layer. The first template has a first hollow pattern, and the first hollow pattern exposes the plurality of pixels. The above method also includes providing the first material. The first material includes a transparent material. The above-mentioned method also includes applying the above-mentioned first material on the above-mentioned substrate through the above-mentioned first template to cover a plurality of pixels of the above-mentioned substrate and fill the above-mentioned plurality of first openings, so that a plurality of first materials formed by the above-mentioned first material are formed. A transparent column is formed on the plurality of pixels of the substrate. The method also includes removing the first template from the first light shielding layer.

According to some embodiments of the present invention, a semiconductor device is provided. The above-described semiconductor device includes a substrate. The above-mentioned substrate has a plurality of pixels. The above-mentioned semiconductor device also includes a light-collimation layer disposed on the above-mentioned substrate. The light collimation layer includes a first light shielding layer disposed on the substrate and a plurality of first transparent pillars disposed on the substrate. The plurality of first transparent pillars cover the plurality of pixels of the substrate. The light-collimating layer also includes a second light-shielding layer disposed on the first light-shielding layer and a plurality of second transparent columns disposed on the plurality of first transparent columns. The plurality of second transparent cylinders cover the plurality of first transparent cylinders.

10, 10', 20, 20': Semiconductor devices

100: Substrate

100T: Top surface of substrate

100B: Bottom surface of substrate

100E: Side of the substrate

102, 102': shading layer

102a: Opening

104: Templates

104a: Opening

106, 106', 206, 206': transparent cylinder

108, 208: light collimation layer

110: Cover

204: Template

204a: Opening

207, 207’: Transparent connection feature

P: pixel

W1, W2, W3, W4: Width

T1, T2, T3: Thickness

H1, H2: height

The embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be noted that the various features are not drawn to scale and are intended to be illustrative only. In fact, the dimensions of elements may be enlarged or reduced to clearly represent the technical features of the embodiments of the present invention.

Figures 1A, 1B, 1C, 1D, 1E, 1F, and 1G are a series of cross-sectional views illustrating a method of forming a semiconductor device according to some embodiments of the present invention.

FIG. 1D' depicts a top view of template 104 in accordance with some embodiments of the present invention.

FIG. 1G' depicts a cross-sectional view of a semiconductor device 10 according to some embodiments of the present invention.

FIG. 1G" depicts a cross-sectional view of a semiconductor device 10' according to some embodiments of the present invention.

Figures 2A, 2B, 2C, 2D, 2E, 2F, and 2G are a series of cross-sectional views illustrating a method of forming a semiconductor device according to some embodiments of the present invention.

Figure 2D' depicts a top view of template 204 in accordance with some embodiments of the present invention.

FIG. 2G' depicts a cross-sectional view of the semiconductor device 20 according to some embodiments of the present invention.

FIG. 2G" illustrates a cross-sectional view of a semiconductor device 20' according to some embodiments of the present invention.

The following disclosure provides many different embodiments or examples for implementing different features of the present invention. The following disclosure describes specific examples of various components and their arrangements to simplify the description. Of course, these specific examples are not intended to be limiting. For example, if the embodiment of the present invention describes that a first feature is formed on or above a second feature, it means that it may include the above-mentioned first feature and the above-mentioned Embodiments in which the second feature is in direct contact may also include embodiments in which additional features are formed between the first feature and the second feature so that the first feature and the second feature may not be in direct contact. In addition, the different examples disclosed below may reuse the same reference symbols and/or labels. These repetitions are for the purpose of simplicity and clarity and are not intended to limit the specific relationship between the various embodiments and/or structures discussed.

Various embodiments of the present invention will be described hereinafter. Similar reference numerals may be used to refer to similar elements. It should be understood that additional operational steps may be performed before, during, or after the method, and in other embodiments of the method, some operational steps may be substituted or omitted.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. It is to be understood that these terms, such as those defined in commonly used dictionaries, should be interpreted to have a meaning consistent with the relevant art and the context or context of the invention and not in an idealized or overly formal manner Interpretation, unless specifically defined in the embodiments of the present invention.

[First Embodiment]

In the method for forming the semiconductor device of this embodiment, a light shielding layer is formed on a substrate and a plurality of openings are formed in the light shielding layer, and then a stencil printing process is used to dispose a transparent material on the substrate to form a plurality of transparent pillars body. The above-mentioned light shielding layer and transparent cylinder can be used as a light collimation layer of a semiconductor device (eg, a fingerprint identification device). Since the cost of the above-mentioned stencil printing process is relatively low, the production cost of the light-collimation layer and the semiconductor device including the above-mentioned light-collimation layer can be reduced.

FIG. 1A illustrates the initial steps of the method for forming the semiconductor device of the present embodiment. As shown in FIG. 1A, a substrate 100 is provided. The substrate 100 may have a top surface 100T and a bottom surface 100B opposite to the top surface 100T, and the side 100E of the substrate 100 may be located between the top surface 100T and the bottom surface 100B.

In some embodiments, the substrate 100 may be made of elemental semiconductors (eg, silicon or germanium), compound semiconductors (eg, silicon carbide (SiC), gallium arsenide (GaAs), indium arsenide (InAs), or indium phosphide (InP)) ), alloy semiconductors (for example: SiGe, SiGeC, GaAsP or GaInP), other suitable semiconductors or a combination of the above. In some embodiments, the substrate 100 may be a semiconductor-on-insulator (SOI) substrate. The semiconductor-on-insulator substrate may include a bottom plate, a buried oxide layer disposed on the bottom plate, and a semiconductor layer disposed on the buried oxide layer. In some embodiments, the substrate 100 may be a semiconductor wafer (eg, a silicon wafer or other suitable semiconductor wafer).

In some embodiments, the substrate 100 may include various p-type doped regions and/or n-type doped regions formed by processes such as ion implantation and/or diffusion. For example, the above-mentioned doped regions may be configured to form transistors, photodiodes and/or light emitting diodes, but the embodiments of the present invention are not limited thereto.

In some embodiments, the substrate 100 may include various isolation features to separate different device regions in the substrate 100 . For example, the isolation features may include shallow trench isolation (STI) features, but the embodiments of the present invention are not limited thereto. In some embodiments, the step of forming the shallow trench isolation may include etching a trench in the substrate 100 and filling the trench with an insulating material (eg, silicon oxide, silicon nitride, or silicon oxynitride). . The filled trenches can have a multi-layered structure (eg: a thermal oxide liner and nitridation filling the trenches) silicon). A chemical mechanical polishing (CMP) process may be performed to polish away excess insulating material and planarize the upper surface of the isolation features.

In some embodiments, the substrate 100 may include various conductive features (eg, lines or vias). For example, the conductive features described above may be formed of aluminum (Al), copper (Cu), tungsten (W), alloys of each thereof, other suitable conductive materials, or a combination thereof.

Please continue to refer to FIG. 1A , in some embodiments, the substrate 100 may include a plurality of pixels P. In some embodiments, the pixel P can convert the received optical signal into a current signal. In some embodiments, the plurality of pixels P of the substrate 100 may be arranged in an array, but the embodiments of the present invention are not limited thereto. For example, in some embodiments, one pixel P of the substrate 100 may include or correspond to at least one photodiode and/or other appropriate elements, but the embodiments of the present invention are not limited thereto. As shown in FIG. 1A, a pixel P may have a width W1. For example, the width W1 may be 2 to 200 μm, but the embodiment of the present invention is not limited thereto.

Next, as shown in FIG. 1B , a light shielding layer 102 is formed on the top surface 100T of the substrate 100 . The light shielding layer 102 may be formed of a light shielding material. For example, the light-shielding material may include photoresist (eg, black photoresist or other suitable non-transparent photoresist), ink (eg, black ink or other suitable non-transparent ink), molding compounds such as : black molding compound or other suitable non-transparent molding compound), solder mask (solder mask, such as: black solder mask or other suitable non-transparent solder mask), epoxy resin black polymer material, Other suitable materials or a combination of the above. In some embodiments, the light shielding layer 102 may include a photocurable material, a thermally curable material, or a combination thereof.

As shown in FIG. 1B, the light shielding layer 102 may have a thickness T1. For example, the thickness T1 may be 2 μm to 150 μm (eg, 5 μm to 100 μm), but the embodiment of the present invention is not limited thereto.

Next, as shown in FIG. 1C , the light shielding layer 102 is patterned to form a plurality of openings 102 a in the light shielding layer 102 . In some embodiments, opening 102a corresponds to pixel P. In other words, in these embodiments, the opening 102a may expose at least a part of the corresponding pixel P. As shown in FIG. 1C, the opening 102a may have a width W2. For example, the width W2 may be 2 to 200 μm, but the embodiment of the present invention is not limited thereto.

In some embodiments, as shown in FIG. 1C , the width W2 of the opening 102 a may be substantially the same as the width W1 of the pixel P. In other words, in these embodiments, the sidewalls of the openings 102a can be aligned with the sidewalls of the corresponding pixels P. In some other embodiments, the width W2 of the opening 102a is greater than the width W1 of the pixel P.

In some embodiments, since the plurality of pixels P of the substrate 100 are arranged in an array, the plurality of openings 102a corresponding to the pixels P are also arranged in an array. The opening 102a may have any suitable shape depending on design requirements. For example, in some embodiments, in the top view, the opening 102a can be rectangular, circular, oval, oblong, hexagonal, irregular, other suitable shapes, or a combination thereof.

In some embodiments, the patterning process for forming the plurality of openings 102a may include a photolithography process. For example, the photolithography process may include mask aligning, exposure, post-exposure baking, developing photoresist, other suitable processes or combination of the above.

Next, as shown in FIG. 1D , the template 104 is placed on the top surface 100T of the substrate 100 and the light shielding layer 102 . In some embodiments, the template 104 may have a plurality of openings 104 a corresponding to the pixels P of the substrate 100 . In other words, in these embodiments, after the step of placing the template 104 on the top surface 100T of the substrate 100 and the light shielding layer 102 , the openings 104 a may expose at least a portion of the corresponding pixels P. In some embodiments, as shown in FIG. 1D, after the step of placing the template 104 on the top surface 100T of the substrate 100 and the light shielding layer 102, the opening 104a communicates with the opening 102a.

As shown in FIG. 1D, the template 104 may have a thickness T2, and the opening 104a may have a width W3. For example, the thickness T2 may be 20 to 200 μm, but the embodiment of the present invention is not limited thereto. For example, the width W3 may be 2 to 200 μm, but the embodiment of the present invention is not limited thereto.

In some embodiments, as shown in FIG. 1D , the width W3 of the opening 104a may be substantially the same as the width W1 of the pixel P. In other words, in these embodiments, the sidewall of the opening 104a can be aligned with the sidewall of the corresponding pixel P. In some other embodiments, the width W3 of the opening 104a is greater than the width W1 of the pixel P. In some embodiments, as shown in FIG. 1D, the width W3 of the opening 104a may be substantially the same as the width W2 of the opening 102a. In other words, in these embodiments, the sidewalls of the openings 104a may be aligned with the sidewalls of the corresponding openings 102a. In some other embodiments, the width W3 of the opening 104a is greater than the width W2 of the opening 102a.

Next, please refer to FIG. 1D', which shows a top view of the template 104. In some embodiments, as shown in FIG. 1D', the opening 104a of the template 104 is A cutout pattern is formed in the template 104 . In the subsequent steps, a material (eg, a transparent material) may be disposed on the top surface 100T of the substrate 100 through the hollow pattern of the template 104 , so that the above-mentioned material on the top surface 100T of the substrate 100 has a pattern corresponding to that of the template 104 . The pattern of the hollow pattern will be explained in detail later.

In some embodiments, since the plurality of pixels P of the substrate 100 are arranged in an array, the plurality of openings 104a corresponding to the pixels P are also arranged in an array. It should be understood that, although the openings 104a are arranged in a 3×3 array in the embodiment shown in FIG. 1D', the embodiment of the present invention is not limited thereto. In some other embodiments, the array in which the openings 104a are arranged may have other suitable numbers of columns and columns depending on design requirements.

In some embodiments, as shown in FIG. 1D', the opening 104a may be substantially rectangular, but the embodiment of the present invention is not limited thereto. In some other embodiments, the opening 104a may be circular, oval, oval, hexagonal, irregular, other suitable shapes, or a combination thereof according to design requirements.

For example, the template 104 may be formed of steel, but the embodiment of the present invention is not limited thereto. For example, the opening 104a may be formed in the template 104 by means of mechanical drilling, but the embodiment of the present invention is not limited thereto.

Next, as shown in FIG. 1E , a plurality of transparent pillars 106 are formed on the substrate 100 . In some embodiments, as shown in FIG. 1E , the transparent pillars 106 are disposed in the openings 102 a and 104 a and cover the pixels P of the substrate 100 . The transparent pillars 106 may be formed of a first material. In some embodiments, the first material may include a transparent material (eg, transparent photoresist, polyimide, other suitable materials, or a combination thereof). In some embodiments, the first material may include a photocurable material, a thermally curable material, or a combination thereof. In some embodiments, the first material may have Such as the fluidity of colloids.

In some embodiments, a stencil printing process may be performed using the stencil 104 to coat (or print) the first material on the top surface 100T of the substrate 100 . In some embodiments, in the above-mentioned stencil printing process, the first material is firstly disposed on the stencil 104 , and then a squeegee or a squeegee is moved on the top surface of the stencil 104 in a direction parallel to the top surface 100T of the substrate 100 . A roller (not shown in the figure), and the above-mentioned scraper or roller applies appropriate pressure to the first material, so that the first material is squeezed from the top surface of the template 104 into the openings 104a and 102a. In some embodiments, since the first material is disposed on the top surface 100T of the substrate 100 through the hollow pattern of the template 104 , the transparent pillars 106 may have a pattern corresponding to the hollow pattern of the template 104 . In some embodiments, the pattern of the transparent pillars 106 is substantially the same as the hollow pattern of the template 104 .

In some embodiments, the light shielding layer 102 and the opening for exposing the pixels P are formed before the step of coating (or printing) the first material on the top surface 100T of the substrate 100 using the stencil 104 in the stencil printing process. 102a, so that the transparent pillars 106 formed of the first material can be accurately arranged above the pixels P, and the light collimation layer (ie, the light collimation layer 108 described later) can be improved. Collimation function.

Next, as shown in FIG. 1F , the template 104 is removed from the substrate 100 and the light shielding layer 102 . In some embodiments, a curing process may be performed to cure the first material of the transparent pillars 106 after the step of removing the template 104 from the substrate 100 and the light shielding layer 102 . For example, the above-mentioned curing process may be a photo-curing process, a thermal-curing process, or a combination thereof.

In some embodiments, as shown in FIG. 1F, the transparent cylinder 106 is and the light shielding layer 102 together can serve as the light collimation layer 108 of the semiconductor device. In some embodiments, the light-shielding layers 102 of the light-collimating layer 108 and the transparent pillars 106 may be staggered.

In some embodiments, the light-shielding layer 102 of the light-collimating layer 108 is black (eg, the light-shielding layer 102 is formed of black photoresist, black ink, black mold compound, or black solder mask material), thus improving the light-collimation layer 108 collimation function.

For example, in some embodiments, a light source such as a light emitting diode (not shown in the figure), a blocking layer (not shown in the figure), and other suitable elements may be disposed on the light-collimating layer 108 Or a combination of the above, and a cover plate 110 (eg, a glass cover plate) is disposed on these optical elements to form a semiconductor device 10 such as a fingerprint identification device (as shown in FIG. 1G ).

In some embodiments, the steps described in FIGS. 1B to 1F may be repeated (eg, repeated twice, three times, or any other appropriate number of times), so that the light-collimating layer 108 of the semiconductor device 10 includes more light-shielding layers and The transparent cylinder is used to improve the collimation function of the light collimation layer 108 . For example, as shown in FIG. 1G′, in some embodiments, the steps described in FIGS. 1B to 1F may be repeated to form a light-shielding layer 102 ′ that is the same or similar to the light-shielding layer 102 on the light-shielding layer 102 , and A transparent cylinder 106 ′ which is the same as or similar to the transparent cylinder 106 is formed on the transparent cylinder 106 . In some embodiments, the steps described in Figures 1B to 1F may be repeated any appropriate number of times to increase the ratio of the sum of the heights of the transparent cylinders on the pixel P to the width of the pixel P (eg, H1/W1 ), by This can enhance the collimation function of the light collimation layer 108 . In some embodiments, the ratio of the sum of the heights of the transparent cylinders on the pixel P to the width of the pixel P (eg, H1/W1 ) may be 2 to 30 (eg, 10 to 30).

In some embodiments, as shown in Figure 1G', the transparent cylinder 106 The top surface of the light shielding layer 102 is higher than the top surface of the light shielding layer 102 . In some embodiments, as shown in FIG. 1G', the top surface of the transparent cylinder 106' is higher than the top surface of the light shielding layer 102'.

In some embodiments, the light shielding layer 102' may directly contact the light shielding layer 102. In some embodiments, the light shielding layer 102 and the light shielding layer 102' may be formed of the same material, but the embodiments of the present invention are not limited thereto. In some other embodiments, the light shielding layer 102 and the light shielding layer 102' may be formed of different materials.

In some embodiments, the transparent cylinder 106' may directly contact the transparent cylinder 106. In some embodiments, the transparent cylinder 106 and the transparent cylinder 106' may be formed of the same material, but the embodiment of the present invention is not limited thereto. In some other embodiments, the transparent pillars 106 and the transparent pillars 106' may be formed of different materials.

To sum up the above, the method for forming a semiconductor device of this embodiment is to form a light shielding layer on a substrate and form a plurality of openings in the light shielding layer, and then use a stencil printing process to dispose a transparent material on the substrate to form a plurality of transparent pillars. The above-mentioned light shielding layer and transparent cylinder can be used as a light collimation layer of a semiconductor device (eg, a fingerprint identification device). Since the cost of the above-mentioned stencil printing process is relatively low, the production cost of the light-collimation layer and the semiconductor device including the above-mentioned light-collimation layer can be reduced. In addition, in some embodiments, by forming a light shielding layer before the step of forming the transparent column, and forming a plurality of openings in the light shielding layer to expose the pixels of the substrate, the transparent column can be accurately arranged on the substrate. Above the pixels, the collimation function of the formed light collimation layer can be improved.

FIG. 1G" shows some variations of the semiconductor device 10 of the present embodiment. It should be noted that, unless otherwise specified, the same or similar elements of these variations and the aforementioned embodiments will be denoted by the same reference numerals , and it forms The method may also be the same or similar to the formation method of the previous embodiment.

As shown in FIG. 1G", one of the differences between the semiconductor device 10' and the semiconductor device 10 is that the top surface of the transparent pillar is flush with the top surface of the light shielding layer. For example, in some embodiments, the transparent After the pillars 106, a planarization process is performed to planarize the transparent pillars 106, so that the top surfaces of the transparent pillars 106 and the top surface of the light shielding layer 102 have substantially the same level. In other words, in these embodiments, the transparent pillars The top surface of the body 106 may be coplanar with the top surface of the light shielding layer 102. Similarly, in some embodiments, a planarization process may be performed after forming the transparent pillars 106' to planarize the transparent pillars 106' such that the transparent pillars 106' The top surface of 106' and the top surface of light shielding layer 102' have substantially the same level. In other words, in these embodiments, the top surface forming transparent pillars 106' may be co-located with the top surface of light shielding layer 102'. For example, the above-mentioned planarization process may include a polishing process, a chemical mechanical polishing process, an etch-back process, other suitable processes, or a combination thereof.

[Second Embodiment]

One of the differences between the second embodiment and the first embodiment is that the method for forming the semiconductor device of the second embodiment uses a template having only a single opening to dispose the first material on the substrate.

It should be noted that, unless otherwise specified, the same or similar elements in this embodiment and the previous embodiments will be denoted by the same reference numerals, and the forming methods thereof may also be the same or similar to those in the previous embodiments.

First, as shown in FIG. 2A, the substrate 100 is provided. Next, as shown in FIGS. 2B and 2C , a light shielding layer 102 is formed on the substrate 100 and a plurality of openings 102 a are formed in the light shielding layer 102 to expose the pixels P of the substrate 100 . It should be understood that, The steps shown in FIGS. 2A to 2C are the same as or similar to the steps shown in FIGS. 1A to 1C, and for the sake of brevity, they will not be repeated here.

Next, as shown in FIG. 2D , the template 204 is placed on the top surface 100T of the substrate 100 and the light shielding layer 102 . In some embodiments, the template 204 may have only a single opening 204a. In some embodiments, the opening 204a corresponds to a plurality of pixels P. In other words, in these embodiments, after the step of placing the template 204 on the top surface 100T of the substrate 100 and the light shielding layer 102 , the openings 204 a may expose the corresponding plurality of pixels P. In some embodiments, as shown in FIG. 2D, after the step of placing the template 204 on the top surface 100T of the substrate 100 and the light shielding layer 102, the opening 204a communicates with the plurality of openings 102a.

As shown in FIG. 2D, the template 204 may have a thickness T3, and the opening 204a may have a width W4. For example, the thickness T3 may be 10 to 100 μm, but the embodiment of the present invention is not limited thereto. For example, the width W4 may be 50 to 550 cm, but the embodiment of the present invention is not limited thereto.

In some embodiments, as shown in FIG. 2D, the width W4 of the opening 204a is greater than the width W1 of the pixel P. In some embodiments, as shown in FIG. 2D, the width W4 of the opening 204a is greater than the width W2 of the opening 102a.

Next, please refer to FIG. 2D', which shows a top view of the template 204. In some embodiments, as shown in Figure 2D', the openings 204a of the template 204 form a hollow pattern in the template 204. In the subsequent steps, the first material of the first embodiment can be disposed on the top surface 100T of the substrate 100 through the hollow pattern of the template 204 , so that the first material on the top surface 100T of the substrate 100 has a shape corresponding to the template. The pattern of the hollow pattern of 204 will be described in detail later.

In some embodiments, as shown in Figure 2D', opening 204a may be large The top is round, but the embodiment of the present invention is not limited to this. In some other embodiments, the opening 204a may be rectangular, oval, oval, hexagonal, irregular, other suitable shapes, or a combination thereof according to design requirements.

For example, the template 204 may be formed of steel, but the embodiment of the present invention is not limited thereto. For example, the openings 204a may be formed in the template 204 by means of mechanical drilling, but the embodiment of the present invention is not limited thereto.

Next, as shown in FIG. 2E , a plurality of transparent pillars 206 and transparent connecting features 207 are formed on the substrate 100 . In some embodiments, as shown in FIG. 2E , the transparent pillars 206 are disposed in the openings 102 a and extend into the openings 204 a , and the transparent pillars 206 cover the pixels P of the substrate 100 . In some embodiments, as shown in FIG. 2E , the transparent connecting features 207 are disposed on the light shielding layer 102 and can connect to the transparent pillars 206 . In other words, in such embodiments, a plurality of transparent pillars 206 may be connected to each other via connecting features 207 .

Transparent pillars 206 and transparent connecting features 207 may be formed of a first material. In some embodiments, the first material may include a transparent material (eg, transparent photoresist, polyimide, other suitable materials, or a combination thereof). In some embodiments, the first material may include a photocurable material, a thermally curable material, or a combination thereof. In some embodiments, the first material may have fluidity such as a colloid.

In some embodiments, a stencil printing process may be performed using the stencil 204 to coat (or print) the first material on the top surface 100T of the substrate 100 . In some embodiments, in the above-mentioned stencil printing process, the first material is first disposed on the stencil 204 , and then a squeegee or a squeegee is moved on the top surface of the stencil 204 in a direction parallel to the top surface 100T of the substrate 100 . A roller (not shown in the figure), and the above-mentioned scraper or roller is used to apply appropriate pressure to the first material, so that the first material The material is extruded from the top surface of template 204 into opening 204a and opening 102a. In some embodiments, since the first material is disposed on the top surface 100T of the substrate 100 through the cutout pattern of the template 204 , the transparent pillars 206 and the transparent connection features 207 may have a pattern corresponding to the cutout pattern of the template 204 . pattern. In some embodiments, the pattern of the transparent pillars 206 and the transparent connecting features 207 is substantially the same as the hollow pattern of the template 204 .

In some embodiments, the light shielding layer 102 and the opening for exposing the pixels P are formed before the step of coating (or printing) the first material on the top surface 100T of the substrate 100 using the stencil 204 in the stencil printing process. 102a, so that the transparent pillars 206 formed of the first material can be accurately arranged above the pixels P, and the light collimation layer (ie, the light collimation layer 208 described later) can be improved. Collimation function.

Next, as shown in FIG. 2F , the template 204 is removed from the substrate 100 and the light shielding layer 102 . In some embodiments, the step of removing the template 204 from the substrate 100 and the light shielding layer 102 may be followed by a curing process to cure the transparent pillars 206 and the first material of the transparent connecting features 207 . For example, the above-mentioned curing process may be a photo-curing process, a thermal-curing process, or a combination thereof.

In some embodiments, as shown in FIG. 2F, the transparent pillars 206, the transparent connecting features 207, and the light shielding layer 102 may collectively serve as a light collimation layer 208 for the semiconductor device. In some embodiments, the light-shielding layers 102 and the transparent pillars 206 of the light-collimating layer 208 may be staggered.

In some embodiments, the light-shielding layer 102 of the light-collimation layer 208 is black (eg, the light-shielding layer 102 is formed of black photoresist, black ink, black mold compound, or black solder mask material), thus improving the light-collimation layer 208 collimation function.

For example, in some embodiments, a light source such as a light emitting diode (not shown in the figure), a blocking layer (not shown in the figure), and other suitable elements may be disposed on the light-collimating layer 208 Or a combination of the above, and a cover plate 110 (eg, a glass cover plate) is disposed on these optical elements to form a semiconductor device 20 such as a fingerprint identification device (as shown in FIG. 2G ).

In some embodiments, the steps described in FIGS. 2B to 2F may be repeated (eg, repeated twice, three times, or any other appropriate number of times), so that the light-collimating layer 208 of the semiconductor device 20 includes more light-shielding layers, Transparent pillars and transparent connection features to enhance the collimation function of the light collimation layer 208 . For example, as shown in FIG. 2G ′, in some embodiments, the steps described in FIGS. 2B to 2F may be repeated to form a light shielding layer 102 ′, the same or similar to the light shielding layer 102 on the substrate 100 . Transparent pillar 206 ′ on transparent pillar 206 and transparent connecting feature 207 ′ which is the same or similar to transparent connecting feature 207 . In some embodiments, the steps described in Figures 2B to 2F may be repeated any suitable number of times to increase the ratio of the sum of the heights of the transparent cylinders on the pixel P to the width of the pixel P (eg, H2/W1), by This can enhance the collimation function of the light collimation layer 208 . In some embodiments, the ratio of the sum of the heights of the transparent cylinders on the pixel P to the width of the pixel P (eg, H2/W1) may be 2 to 30 (eg, 10 to 30).

In some embodiments, as shown in FIG. 2G', the top surface of the transparent pillar 206 is higher than the top surface of the light shielding layer 102. In some embodiments, as shown in Figure 2G', the top surface of the transparent cylinder 206' is higher than the top surface of the light shielding layer 102'.

In some embodiments, transparent connection features 207 are provided between the light shielding layer 102' In some embodiments, the light shielding layer 102 and the light shielding layer 102' may be formed of the same material, but the embodiments of the present invention are not limited thereto. In some other embodiments, the light shielding layer 102 and the light shielding layer 102' may be formed of different materials.

In some embodiments, the transparent cylinder 206' may directly contact the transparent cylinder 206. In some embodiments, the transparent cylinder 206 and the transparent cylinder 206' may be formed of the same material, but the embodiment of the present invention is not limited thereto. In some other embodiments, the transparent pillars 206 and the transparent pillars 206' may be formed of different materials.

To sum up the above, the method for forming a semiconductor device of this embodiment is to form a light shielding layer on a substrate and form a plurality of openings in the light shielding layer, and then use a stencil printing process to dispose a transparent material on the substrate to form a plurality of transparent pillars. The above-mentioned light shielding layer and transparent cylinder can be used as a light collimation layer of a semiconductor device (eg, a fingerprint identification device). Since the cost of the above-mentioned stencil printing process is relatively low, the production cost of the light-collimation layer and the semiconductor device including the above-mentioned light-collimation layer can be reduced. In addition, in some embodiments, by forming a light shielding layer before the step of forming the transparent column, and forming a plurality of openings in the light shielding layer to expose the pixels of the substrate, the transparent column can be accurately arranged on the substrate. Above the pixels, the collimation function of the formed light collimation layer can be improved.

FIG. 2G" shows some variations of the semiconductor device 20 of the present embodiment. It should be noted that, unless otherwise specified, the same or similar elements of these variations and the foregoing embodiments will be denoted by the same reference numerals , and its formation method can be the same or similar to the formation method of the foregoing embodiment.

As shown in FIG. 2G", one of the differences between the semiconductor device 20' and the semiconductor device 20 is that the top surface of the transparent pillar is flush with the top surface of the light shielding layer. For example, in some embodiments, the transparent After cylinder 206 A planarization process is performed to planarize the transparent pillars 206 so that the top surfaces of the transparent pillars 206 and the top surfaces of the light shielding layers 102 have substantially the same level. In other words, in such embodiments, the top surfaces of the transparent pillars 206 may be coplanar with the top surfaces of the light shielding layer 102 . In some embodiments, the planarization process described above also removes the transparent connection features 207 . Similarly, in some embodiments, after forming the transparent pillars 206', a planarization process may be performed to planarize the transparent pillars 206', so that the top surfaces of the transparent pillars 206' and the top surface of the light shielding layer 102' have approximately the same thickness. the same level. In other words, in such embodiments, the top surfaces forming the transparent pillars 206' may be coplanar with the top surfaces of the light shielding layer 102'. In some embodiments, the planarization process described above also removes the transparent connection features 207'.

It should be understood that although the top surface of the transparent cylinder 206 is flush with the top surface of the light shielding layer 102 and the top surface of the transparent cylinder 206' is flush with the top surface of the light shielding layer 102' The surface is flush, but the embodiments of the present invention are not limited thereto. For example, in some embodiments, the top surface of the transparent column 206 is flush with the top surface of the light shielding layer 102, and the top of the transparent column 206' The surface is then higher than the top surface of the light shielding layer 102' and the transparent connecting features 207' are not removed. For example, in some embodiments, the top surface of the transparent pillars 206' is flush with the top surface of the light shielding layer 102' , while the top surface of the transparent pillar 206 is higher than the top surface of the light shielding layer 102 and the transparent connecting feature 207 is not removed.

It should be understood that, in some embodiments, the transparent pillars of the light-collimating layer may be formed via a plurality of templates having different hollow patterns. For example, in some embodiments, the transparent pillars 106 may be formed on the pixels P of the substrate 100 using the template 104 of the first embodiment, and then the transparent pillars 106 may be formed using the template 204 of the second embodiment. Transparent cylinder 206 .

To sum up the above, in the method for forming a semiconductor device according to the embodiment of the present invention, a light shielding layer is formed on a substrate and a plurality of openings are formed in the light shielding layer, and then a stencil printing process is used to dispose a transparent material on the substrate to form a plurality of transparent pillars . The above-mentioned light shielding layer and transparent cylinder can be used as a light collimation layer of a semiconductor device (eg, a fingerprint identification device). Since the cost of the above-mentioned stencil printing process is relatively low, the production cost of the light-collimation layer and the semiconductor device including the above-mentioned light-collimation layer can be reduced. In addition, in some embodiments, by forming a light shielding layer before the step of forming the transparent column, and forming a plurality of openings in the light shielding layer to expose the pixels of the substrate, the transparent column can be accurately arranged on the substrate. Above the pixels, the collimation function of the formed light collimation layer can be improved.

The foregoing context outlines the features of many of the embodiments so that those skilled in the art may better understand the various aspects of the embodiments of the invention. It should be understood by those skilled in the art that other processes and structures can be easily designed or modified based on the embodiments of the present invention to achieve the same purpose and/or to achieve the embodiments described herein. the same advantages. Those skilled in the art should also understand that these equivalent structures do not depart from the spirit and scope of the embodiments of the present invention. Various changes, substitutions or modifications may be made to the embodiments of the present invention without departing from the spirit and scope of the embodiments of the present invention.

Furthermore, each claim of this disclosure may be a separate embodiment, and the scope of this disclosure includes each claim and each embodiment of this disclosure in combination with each other.

100‧‧‧Substrate

100T‧‧‧Top surface of substrate

100B‧‧‧Bottom surface of substrate

100E‧‧‧Side of the substrate

102‧‧‧Light shielding layer

102a‧‧‧Opening

104‧‧‧Template

104a‧‧‧Opening

T1, T2‧‧‧Thickness

W1, W2, W3‧‧‧Width

P‧‧‧Pixel

Claims (6)

A method for forming a semiconductor device, comprising: providing a substrate, wherein the substrate includes a plurality of pixels; forming a first light shielding layer on the substrate, wherein the first light shielding layer and the pixels are on a surface of the substrate The normal direction is completely staggered; a first photolithography process is performed to pattern the first light shielding layer to form a plurality of first openings in the first light shielding layer, wherein the first openings expose the first openings of the substrate pixel; placing a first stencil on the first light-shielding layer, wherein the first stencil has a first openwork pattern, the first openwork pattern has only one opening and exposes the some pixels, and the opening corresponds to more than one of the pixels; provide a first material, wherein the first material includes a transparent material; apply the first material on the substrate through the first template to covering the pixels of the substrate and filling the first openings, so that a plurality of first transparent pillars formed of the first material are formed on the pixels of the substrate; and the first template is self The first light shielding layer is removed. The method for forming a semiconductor device as described in item 1 of the claimed scope further comprises: performing a planarization process to planarize the first transparent pillars, so that the top surfaces of the transparent pillars and the first light shielding layer are in contact with each other. Top surface is flush. The method for forming a semiconductor device as described in claim 1, wherein a width of the opening of the first hollow pattern is larger than a width of one of the pixels a width. The method for forming a semiconductor device as described in claim 1, wherein the transparent material comprises a photocurable material, a thermally curable material, or a combination thereof. The method for forming a semiconductor device according to claim 1, further comprising: forming a second light-shielding layer on the first light-shielding layer after the step of removing the first template from the first light-shielding layer; on the first transparent pillars; performing a second photolithography process to pattern the second light shielding layer to form a plurality of second openings in the second light shielding layer, wherein the second openings expose the a first transparent cylinder; placing the first template on the second light shielding layer, wherein the first hollow pattern of the first template exposes the first transparent cylinders; providing the first material; through the The first template coats the first material on the substrate to cover the first transparent pillars and fill the second openings, so that a plurality of second transparent pillars formed of the first material are formed on the on the first transparent cylinders; and removing the first template from the second light shielding layer. The method for forming a semiconductor device as described in claim 1, further comprising: forming a second light-shielding layer on the first light-shielding layer after the step of removing the first template from the first light-shielding layer; On the first transparent pillars; perform a second photolithography process to pattern the second light shielding layer for the second shielding A plurality of second openings are formed in the light layer, wherein the second openings expose the first transparent pillars; a second template is placed on the second light shielding layer, wherein the second template has a second a hollow pattern, the second hollow pattern exposes the first transparent pillars, and the first hollow pattern is different from the second hollow pattern; the first material is provided; the first material is coated through the second template on the substrate to cover the first transparent pillars and fill the second openings, so that a plurality of second transparent pillars formed of the first material are formed on the first transparent pillars; and The second template is removed from the second light shielding layer.

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