Semiconductor device, semiconductor image sensor, and method of manufacturing the same

Abstract

The semiconductor device includes: a first type of light sensing unit, wherein each example of the first type of light sensing unit is operable to receive a first amount of radiation; and a second type of light sensing unit, wherein each example of the second type of light sensing unit is operable to receive a second amount of radiation, and the second type of light sensing unit and the first type of light sensing unit are arranged in an array to form a pixel sensor. The first amount of radiation is less than the second amount of radiation, and at least a first example of the first type of light sensing unit is adjacent to a second example of the first type of light sensing unit. Embodiments of the present invention also relate to a semiconductor image sensor and a method of manufacturing a semiconductor device.

Description

Technical Field

[0001] Embodiments of the present invention relate to semiconductor image sensors, semiconductor devices, and methods of manufacturing the same. Background Art

[0002] Semiconductor image sensors are used to sense light. Semiconductor image sensors utilize a pixel array in a substrate, including photodiodes and transistors that can absorb radiation projected towards the substrate and convert the sensed radiation into an electrical signal.

[0003] Among other things, the performance of a semiconductor image sensor depends on its quantum efficiency and optical crosstalk. The quantum efficiency of an image sensor represents the number of electrons generated per incident photon number in the image sensor. Optical crosstalk occurs when some photons incident on a pixel are absorbed by another pixel.

[0004] Therefore, although existing semiconductor structures of image sensors and conventional methods of manufacturing image sensors are generally sufficient to meet their intended purposes, they are not entirely satisfactory in every aspect. Summary of the Invention

[0005] Some embodiments of the present invention provide a semiconductor device including: a plurality of light sensing units of a first type, wherein each of the plurality of light sensing units of the first type is operable to receive a first amount of radiation; and a plurality of light sensing units of a second type, wherein each of the plurality of light sensing units of the second type is operable to receive a second amount of radiation, and the plurality of light sensing units of the second type and the plurality of light sensing units of the first type are arranged in an array to form a pixel sensor, wherein the first amount of radiation is less than the second amount of radiation, and at least a portion of a first example of the light sensing units of the first type of the plurality of light sensing units of the first type is adjacent to a second example of the light sensing units of the first type of the plurality of light sensing units of the first type.

[0006] Some other embodiments of the present invention provide a semiconductor image sensor including: a pixel sensor array, wherein the pixel sensor array includes a first pixel sensor and a second pixel sensor, and the first pixel sensor includes: a light sensing unit of a first type; and a light sensing unit of a second type, wherein the light sensing unit of the first type and the light sensing unit of the second type are arranged in a sub-array, wherein the light sensing unit of the first type is operable to receive less radiation compared to the light sensing unit of the second type, and at least a portion of the light sensing unit of the first type is adjacent to the second pixel sensor.

[0007] Some embodiments of the present invention provide a method of manufacturing a semiconductor device, including: disposing a plurality of light sensing units of a first type on a substrate; disposing a plurality of light sensing units of a second type disposed on the substrate, wherein each of the plurality of light sensing units of the first type is operable to receive less radiation compared to each of the plurality of light sensing units of the second type, and disposing the plurality of light sensing units of the second type includes disposing at least one of the plurality of light sensing units of the second type adjacent to a portion of at least one of the plurality of light sensing units of the first type; disposing a first isolation structure between one of the plurality of light sensing units of the first type and one of the plurality of light sensing units of the second type; disposing a second isolation structure between adjacent light sensing units of the first type among the plurality of light sensing units of the first type; and disposing a reflective layer over the plurality of light sensing units of the first type. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Aspects of the present invention are best understood from the following detailed description when read with the accompanying drawings. It should be noted that, in accordance with standard practice in the industry, the various components are not drawn to scale. In fact, for clarity of discussion, the dimensions of the various components may be arbitrarily increased or decreased.

[0009] FIG. 1(a) shows a top view of a semiconductor device in accordance with some embodiments of the present invention. FIG. 1(b) shows a cross-sectional view taken along line A-A' of the semiconductor device in FIG. 1(a).

[0010] FIG. 2(a) shows a top view of a semiconductor device in accordance with some embodiments of the present invention. FIG. 2(b) shows a cross-sectional view taken along line B-B' of the semiconductor device in FIG. 2(a).

[0011] FIG. 3(a) shows a top view of a semiconductor device in accordance with some embodiments of the present invention. FIG. 3(b) shows a cross-sectional view taken along line C-C' of the semiconductor device in FIG. 3(a).

[0012] FIG. 4(a) shows a top view of a semiconductor device in accordance with some embodiments of the present invention. FIG. 4(b) shows a cross-sectional view taken along line D-D' of the semiconductor device in FIG. 4(a).

[0013] Figure 5 Shows a cross-sectional view of a semiconductor device in accordance with some embodiments of the present invention.

[0014] Figure 6 Shows a cross-sectional view of a semiconductor device in accordance with some embodiments of the present invention.

[0015] Figure 7 Shows a cross-sectional view of a semiconductor device in accordance with some embodiments of the present invention.

[0016] Figure 8A , Figure 8B , Figure 8C , Figure 8D , Figure 8E , Figure 8F , Figure 8G and Figure 8H illustrate a method of manufacturing a semiconductor device such as those shown in FIGS. 2(a), 2(b), 3(a) and 3(b). DETAILED DESCRIPTION

[0017] The following disclosure provides many different embodiments or examples for implementing different components of the provided subject matter. Specific examples of components and arrangements are described below to simplify the present invention. Of course, these are merely examples and are not intended to limit the present invention. For example, in the following description, forming a first component above or on a second component may include embodiments in which the first and second components are in direct contact, and may also include examples in which additional components may be formed between the first and second components such that the first and second components may not be in direct contact. In addition, the present invention may repeat reference numerals and / or characters in various embodiments. This repetition is for the purpose of simplicity and clarity and does not in itself indicate a relationship between the various embodiments and / or configurations discussed.

[0018] Moreover, for ease of description, spatially relative terms such as "under", "below", "lower", "above", "upper", etc. may be used herein to describe the relationship of one element or component to another (or other) element or component as shown in the figures. In addition to the orientation shown in the figures, spatially relative terms are intended to include different orientations of the device in use or operation. The device may be oriented in other ways (rotated 90 degrees or in other orientations), and the spatially relative descriptors used herein may be interpreted accordingly.

[0019] As used herein, terms such as "first", "second", and "third" describe various elements, components, regions, layers, and / or portions, and these elements, components, regions, layers, and / or portions should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer, or portion from another element, component, region, layer, or portion. Unless the context clearly indicates otherwise, terms such as "first", "second", and "third" used herein do not imply an order or sequence.

[0020] As used herein, the terms "about," "substantially," "generally," and "approximately" are used to describe and account for small variations. When used in conjunction with an event or circumstance, these terms can refer to instances where the event or circumstance occurs precisely as well as instances where it occurs very nearly. For example, when used in conjunction with a numerical value, the term can refer to a variation range of less than or equal to ±10% of that numerical value, such as less than or equal to ±5%, less than or equal to ±4%, less than or equal to ±3%, less than or equal to ±2%, less than or equal to ±1%, less than or equal to ±0.5%, less than or equal to ±0.1%, less than or equal to ±0.05%. For example, if the difference between two numerical values is less than or equal to ±10% of the average value, such as less than or equal to ±5%, less than or equal to ±4%, less than or equal to ±3%, less than or equal to ±2%, less than or equal to ±1%, less than or equal to ±0.5%, less than or equal to ±0.1%, or less than or equal to ±0.05%, then the two numerical values can be considered "substantially" the same or equal. For example, "substantially" parallel can refer to an angular variation range of less than or equal to ±10° relative to 0°, such as less than or equal to ±5°, less than or equal to ±4°, less than or equal to ±3°, less than or equal to ±2°, less than or equal to ±1°, less than or equal to ±0.5°, less than or equal to ±0.1°, or less than or equal to ±0.05°. For example, "substantially" perpendicular can refer to an angular variation range of less than or equal to ±10° relative to 90°, such as less than or equal to ±5°, less than or equal to ±4°, less than or equal to ±3°, less than or equal to ±2°, less than or equal to ±1°, less than or equal to ±0.5°, less than or equal to ±0.1°, or less than or equal to ±0.05°.

[0021] Some embodiments of an image sensor use at least two pixel sensors classified by incident radiation to form repeating units arranged in an array. For example, some embodiments of an image sensor include a first pixel sensor for sensing long wavelengths (e.g., infrared (IR) light and red light) and a second pixel sensor for sensing short wavelengths (e.g., green light and blue light). Additionally, in some embodiments, each pixel sensor also uses at least two light-sensing units classified by the amount of incident radiation (or light) to be received. For example, as used herein, the first light-sensing unit refers to a light-sensing unit that is operable to receive less radiation (or light) over a given period of time compared to the second light-sensing unit.

[0022] As the size of the image sensor becomes smaller, crosstalk becomes a major issue between adjacent pixel sensors and further between adjacent light sensing units included in the adjacent pixel sensors. As the surface area for receiving light becomes smaller, the light sensing units become more sensitive to crosstalk because there is less signal (light directly received by the sensor) compared to the noise (crosstalk between adjacent pixel sensors). Crosstalk can have an adverse effect on the amount of light received by the light sensing units. Pixel sensor designs that reduce crosstalk provide increased light absorption efficiency, which is particularly beneficial for low levels of incident light.

[0023] FIG. 1(a) shows a top view of a semiconductor device 101 according to some embodiments of the present invention. FIG. 1(b) shows a cross-sectional view taken along line A-A' of the semiconductor device 101 in FIG. 1(a).

[0024] The semiconductor device 101 of FIG. 1(a) includes a plurality of first light sensing units 103a, 103b and a plurality of second light sensing units 105a, 105b, 105c, 105d.

[0025] The semiconductor device 101 has a first surface 101a and a second surface 101b opposite to the first surface 101a. According to some embodiments, the semiconductor device 101 is a bulk semiconductor substrate (e.g., a bulk silicon (Si) substrate), a silicon-on-insulator (SOI) substrate, or a wafer. In some embodiments, the semiconductor device 101 is a wafer.

[0026] The first light sensing units 103a, 103b are operable to receive radiation projected towards the first light sensing units 103a, 103b and convert the radiation into an electrical signal. In some embodiments, the first light sensing units 103a, 103b are operable to detect different wavelengths (colors) from incident light (e.g., blue (B) light, green (G) light, and red (R) light). According to some embodiments, the first light sensing units 103a, 103b are components or parts of a pixel sensor. In some embodiments, the first light sensing units 103a, 103b are arranged in a sub-array in the pixel sensor.

[0027] The second photosensing units 105a, 105b, 105c, 105d are operable to receive radiation projected towards the second photosensing units 105a, 105b, 105c, 105d and convert the radiation into an electrical signal. In some embodiments, the second photosensing units 105a, 105b, 105c, 105d are operable to detect different wavelengths (colors) from incident light (e.g., blue (B) light, green (G) light, and red (R) light). As used herein, the second photosensing units 105a, 105b, 105c, 105d refer to photosensing units that are operable to receive more radiation compared to the first photosensing units 103a, 103b. In other words, the first photosensing units 103a, 103b refer to photosensing units that are operable to receive less radiation compared to the second photosensing units 105a, 105b, 105c, 105d. In some embodiments, the first photosensing units 103a, 103b are operable to receive less radiation through a reflective layer 119 disposed over the first photosensing units 103a, 103b. In some embodiments, the second photosensing units 105a, 105b, 105c, 105d are also components or parts of pixel sensors. According to some embodiments, the second photosensing units 105a, 105b, 105c, 105d and the first photosensing units 103a, 103b are arranged in sub-arrays in a pixel sensor.

[0028] The first light sensing units 103a, 103b and the second light sensing units 105a, 105b, 105c, 105d constitute a pixel sensor. According to some embodiments, the pixel sensor includes at least one first light sensing unit 103a, 103b and at least one second light sensing unit 105a, 105b, 105c, 105d. In some embodiments, the first light sensing units 103a, 103b are arranged adjacent to at least two second light sensing units 105a, 105b, 105c, 105d. In some embodiments, the first light sensing units 103a, 103b are arranged adjacent to two, three, four, five, six, seven or eight second light sensing units 105a, 105b, 105c, 105d. In some embodiments, the first light sensing units 103a, 103b are surrounded by the second light sensing units 105a, 105b, 105c, 105d surrounding the periphery of the first light sensing units 103a, 103b. In some embodiments, the second light sensing units 105a, 105b, 105c, 105d are circular regions surrounded by the first light sensing units 103a, 103b. According to some embodiments, in the pixel sensor, the first light sensing units 103a, 103b are surrounded by at least two second light sensing units 105a, 105b, 105c, 105d. In some embodiments, the first light sensing units 103a, 103b are surrounded by three second light sensing units 105a, 105b, 105c, which constitute a repeating pixel sensor unit. In some embodiments, the repeating pixel sensor unit includes the first light sensing units 103a, 103b surrounded by four second light sensing units 105a, 105b, 105c, 105d.

[0029] According to some embodiments, the pixel sensor composed of the first light sensing units 103a and the second light sensing units 105a, 105b, 105c, 105d is one of a blue light sensor, a green light sensor, and a red light sensor.

[0030] According to some embodiments, the first isolation structures 111a, 111b, 111c are also disposed between the first light sensing units 103a, 103b and the adjacent second light sensing units 105a, 105b, so that the light projected toward the second light sensing units 105a, 105b is blocked and does not reach the first light sensing units 103a, 103b. As a result, the crosstalk interference from the adjacent second light sensing units 105a, 105b to the first light sensing units 103a, 103b is reduced. According to some embodiments, the first isolation structures 111a, 111b, 111c have a substantially rectangular, trapezoidal, elongated oval or any other suitable shape. In some embodiments, the first isolation structures 111a, 111b, 111c include pads 107a, 107b and insulating structures 109a, 109b.

[0031] The pads 107a, 107b are arranged to be conformal with the trenches 108a, 108b adjacent to the first surface 101a of the semiconductor device 101.

[0032] In some embodiments, the pads 107a, 107b comprise a low refractive index (low-n) material having a refractive index (n) less than that of the color filter, high-k (high dielectric constant) material, or a combination thereof operable for the first photosensing unit 103a. In some embodiments, the low-n material comprises, for example, SiO2, HfO2, or a combination thereof. In some embodiments, the high-k material comprises, for example, HfO2, Al2O3, TiO2, HfZrO, Ta2O3, Ta2O5, HfSiO4, ZrO2, ZrSiO2, Ln2O3, or a combination thereof.

[0033] The insulating structures 109a, 109b are arranged adjacent to the pads 107a, 107b. In some embodiments, the insulating structures 109a, 109b are arranged on the pads 107a, 107b. In some embodiments, the insulating structures 109a, 109b comprise a low-n material having a refractive index (n) less than that of the color filter operable for the first photosensing unit 103a. In some embodiments, the low-n material comprises, for example, SiO2, HfO2, or a combination thereof. In some embodiments, the insulating structures 109a, 109b further comprise a low-k material (e.g., a glass material composed of fluorine, silicon, and oxygen), an oxide layer, and a reflective material to prevent radiation projected toward one side of the insulating structures 109a, 109b from entering the other side of the insulating structures 109a, 109b, so as to further reduce crosstalk between the first photosensing units 103a, 103b and the second photosensing units 105a, 105b.

[0034] Logic devices 123a, 123b such as transistors are also provided in the semiconductor device 101 and are operable to ensure readings of the first photosensing units 103a, 103b, the second photosensing units 105a, 105b, 105c, 105d, or both. In some embodiments, the logic devices 123a, 123b are arranged adjacent to the first photosensing units 103a, 103b, the second photosensing units 105a, 105b, 105c, 105d, or both. In some embodiments, the logic devices 123a, 123b are arranged adjacent to the third surface 101c opposite to the first surface 101a of the semiconductor device 101 and close to the back ends of the first photosensing units 103a, 103b and the second photosensing units 105a, 105b, 105c, 105d.

[0035] According to some embodiments, the circuit stack 129 is also disposed adjacent to the logic devices 123a, 123b. In some embodiments, the circuit stack 129 is disposed adjacent to the second surface 101b of the semiconductor device 101. In some embodiments, the circuit stack 129 is a back-end-of-line (BEOL) metallization stack. In some embodiments, the circuit stack 129 is electrically connected to the logic devices 123a, 123b through at least one conductive via, at least one conductive contact, or a combination thereof. In some embodiments, the circuit stack 129 includes at least one metal layer 127 and at least one dielectric layer 125.

[0036] The metal layer 127 is disposed in the dielectric layer 125. In some embodiments, the metal layer 127 includes, for example, copper, tungsten, aluminum, other metals, or metal alloys thereof.

[0037] According to some embodiments, the dielectric layer 125 includes a low-k material (e.g., a dielectric material having a dielectric constant less than 3.9).

[0038] FIG. 2(a) shows a top view of a semiconductor device 201 according to some embodiments of the present invention. The semiconductor device 201 shown in FIG. 2(a) is similar to that shown in FIG. 1(a), with differences including that at least a portion of the first photosensing unit 203a is adjacent to at least one of the first photosensing units 203b, 203c, 203d. FIG. 2(b) shows a cross-sectional view taken along line B-B' of the semiconductor device 201 in FIG. 2(a).

[0039] Unlike the semiconductor device 101 shown in FIGS. 1(a) and 1(b), the semiconductor device 201 shown in FIGS. 2(a) and 2(b) includes at least one first photosensing unit 203a disposed adjacent to at least one of the first photosensing units 203b, 203c, 203d. In some embodiments, at least one side of the first photosensing unit 203a is disposed adjacent to at least one of the first photosensing units 203b, 203c, 203d. In some embodiments, at least two sides of the first photosensing unit 203a are disposed adjacent to at least one of the first photosensing units 203b, 203c, 203d. In some embodiments, a first example of the first photosensing unit 203a may be adjacent to a second example of the first photosensing unit 203b on a first side and adjacent to a third first sensing unit 203d on a second side adjacent to the first side. In some embodiments, at least a portion of the first photosensing unit 203a is surrounded by at least one of the first photosensing units 203b, 203c, 203d. In some embodiments, at least a portion of the first photosensing unit 203a is surrounded by at least two of the first photosensing units 203b, 203c. In some embodiments, at least a portion of the first photosensing unit 203a is surrounded by at least three of the first photosensing units 203b, 203c, 203d.

[0040] At least a portion of the first photosensing unit 203a is surrounded by at least a portion of another first photosensing unit 203b, 203c, 203d, and at least a portion of the first photosensing unit 203a is surrounded by at least a portion of the second photosensing unit 205a. In some embodiments, at least a portion of the first photosensing unit 203a is surrounded by at least a portion of another first photosensing unit 203b, 203c, 203d, and the remaining portion of the first photosensing unit 203a is surrounded by at least a portion of the second photosensing unit 205a.

[0041] In some embodiments, the first light sensing unit 203a and the second light sensing unit 205a form a pixel sensor. According to some embodiments, the pixel sensor includes at least one first light sensing unit 203a and at least one second light sensing unit 205a. In some embodiments, the first light sensing unit 203a is adjacent to at least one second light sensing unit 205a. In some embodiments, the first light sensing unit 203a is arranged to be adjacent to one, two, three, four, or five second light sensing units 205a, 205b, 205c. In some embodiments, the first light sensing unit 203a is partially surrounded by the second light sensing units 205a, 205b, 205c. In some embodiments, in the pixel sensor, the first light sensing unit 203a is surrounded by at least one second light sensing unit 205a. In some embodiments, the repeating pixel sensor unit includes a first light sensing unit 203a surrounded by a second light sensing unit 205a. In some embodiments, the first light sensing unit 203a is arranged to be adjacent to the corner of the pixel sensor. In some embodiments, the first light sensing unit 203a is located at the corner of the pixel sensor. In some embodiments, the projection areas of the first light sensing units 203a, 203b and the projection areas of the second light sensing units 205a, 205b have a ratio of about 1:3.

[0042] In some embodiments, the first light sensing unit 203a is surrounded by one second light sensing unit 205a of the same pixel sensor and the other second light sensing units 205b, 205c of another pixel sensor. In some embodiments, the portion of the first light sensing unit 203a surrounded by the second light sensing unit 205a of the same pixel sensor is not greater than the portion of the first light sensing unit 203a surrounded by the first light sensing units 203b, 203c, 203d.

[0043] By arranging at least a portion of the first light sensing unit 203a to be adjacent to at least one first light sensing unit 203b, as the area where the second light sensing unit 205b surrounds the first light sensing unit 203a decreases, crosstalk is reduced due to the reflection or refraction of light from the adjacent second light sensing unit 205a to the first light sensing unit 203a. As a result, since the light interference (e.g., crosstalk) from the adjacent second light sensing units 205a, 205b is reduced, the photosensitivity of the first light sensing units 203a, 203b increases.

[0044] Referring to FIG. 2(b), in some embodiments where the first light sensing unit 203a is arranged to be adjacent to another first light sensing unit 203b, the reflective layer 219 extends from the projection area of the first light sensing unit 203a to the projection area of the first light sensing unit 203b.

[0045] FIG. 3(a) shows a top view of a semiconductor device 301 according to some embodiments of the present invention. The semiconductor device 301 shown in FIG. 3(a) is similar to that shown in FIG. 2(a), and compared with Figure 2a that shown, the differences include that the side surface 303e of the first photosensing unit 303a is curved, and through this curvature, the portion of the first photosensing unit 303a surrounded by the second photosensing unit 305a of the same pixel sensor can be further reduced. In some embodiments, the portion of the first photosensing unit 303a surrounded by the second photosensing unit 305a of the same pixel sensor is smaller than the portion of the first photosensing unit 303a surrounded by the first photosensing units 303b, 303c, 303d. As a result, compared with that shown in FIG. 2(a), since the portion of the first photosensing unit 303a surrounded by the second photosensing unit 305a of the same pixel sensor can be further reduced, the above-mentioned crosstalk interference is further reduced.

[0046] FIG. 3(b) shows a cross-sectional view taken along line C-C' of the semiconductor device 301 in FIG. 3(a). The structure of the semiconductor device 301 shown in FIG. 3(b) is similar to that shown in FIG. 2(b), and will not be described in detail for the sake of brevity.

[0047] FIG. 4(a) shows a top view of a semiconductor device 401 according to some embodiments of the present invention. The semiconductor device 401 shown in FIG. 4(a) is similar to that shown in FIG. 2(a), and the differences include that third photosensing units 431a, 431b are provided between the first photosensing units 403a, 403b and the second photosensing units 405a, 405b. FIG. 4(b) shows a cross-sectional view taken along line D-D' of the semiconductor device 401 in FIG. 4(a).

[0048] In some embodiments, the third photosensing units 431a, 431b are different from the first photosensing units 403a, 403b and the second photosensing units 405a, 405b. Thus, the third photosensing units 431a, 431b can be distinguished from the first photosensing units 431a, 431b and do not cause crosstalk like the second photosensing units 405a, 405b. In some embodiments, the third photosensing units 431a, 431b are operable to receive radiation projected toward the third photosensing units 431a, 431b and convert the radiation into an electrical signal. In some embodiments, compared with the first photosensing units 403a, 403b, the second photosensing units 405a, 405b, or both, the third photosensing units 431a, 431b are operable to receive less radiation projected toward them and convert the radiation into an electrical signal. As a result, compared with the second photosensing units 405a, 405b, since the third photosensing units 431a, 431b can receive less radiation projected toward them, they can cause less crosstalk than that caused by the second photosensing units 405a, 405b, which further reduces the crosstalk interference to the first photosensing units 403a, 403b compared with the second photosensing units 405a, 405b.

[0049] In addition, since disposing the third photosensing units 431a, 431b between the first photosensing units 403a, 403b and the second photosensing units 405a, 405b can increase the distance between them and move the crosstalk sources of the second photosensing units 405a, 405b away from the first photosensing units 403a, 403b, there is less crosstalk that can reach the first photosensing units 403a, 403b, which further improves the sensitivity of the first photosensing units 403a, 403b.

[0050] Figure 5 A cross-sectional view of a semiconductor device 501 according to some embodiments of the present invention is shown. Figure 5 The semiconductor device 501 shown is similar to those shown in FIGS. 1(a), 2(a), 3(a), and 4(a), with differences including that the first isolation structure 511b has a larger projection area compared with a conventional design.

[0051] In some embodiments, such as those shown in FIG. 1(b), where the first isolation structure 511b is disposed to separate the first photosensing unit 503a from the second photosensing unit 505b, the projection area of the first isolation structure 511b is enlarged compared with a conventional design. Thus, there is less crosstalk transmitted through it and reaching the first photosensing units 503a, 503b. As a result, the crosstalk interference from the adjacent second photosensing unit 505b is reduced.

[0052] In some embodiments, such as those shown in FIGS. 2(b), 3(b), and 4(b), where a first isolation structure 511b is provided to separate a first photosensing unit 503a from a second photosensing unit 505b, and a second isolation structure 511a is provided to separate the first photosensing unit 503a from another first photosensing unit 503b, by setting the first isolation structure 511b to have a larger projection area than the second isolation structure 511a, crosstalk interference from the adjacent second photosensing unit 505b is reduced.

[0053] In some embodiments, the first isolation structure 511b includes a pad 507b and an insulating structure 509b. In some embodiments, the second isolation structure 511a includes a pad 507a and an insulating structure 509a. The pads 507b, 507a and the insulating structures 509b, 509a are similar to those described above and will not be elaborated for the sake of brevity.

[0054] Figure 6 A cross-sectional view of a semiconductor device 601 according to some embodiments of the present invention is shown. Figure 6 The semiconductor device 601 shown is similar to those shown in FIGS. 1(a), 2(a), 3(a), and 4(a), with differences including that a reflective layer 619 extends from the projection area of the first photosensing unit 603a to the projection area of the adjacent second photosensing unit 605b.

[0055] By setting the reflective layer 619 to extend from the projection area of the first photosensing unit 603a to the projection area of the adjacent second photosensing unit 605b, the reflective layer 619 reduces the light projected toward the second photosensing unit 605b and the crosstalk generated by the first photosensing unit 603a. However, it should be noted that in the embodiments where the extension of the reflective layer 619 is designed, the reduction of the light of the reflective layer 619 toward the second photosensing unit 605b does not affect the intended purpose of the second photosensing unit 605b, that is, receiving more radiation than the first photosensing unit 603a.

[0056] Figure 7 A cross-sectional view of a semiconductor device 701 according to some embodiments of the present invention is shown. Figure 7 The semiconductor device 701 shown is similar to those shown in FIGS. 1(a), 2(a), 3(a), and 4(a), with differences including that a first surface 733 of the second photosensing unit 705b has roughness.

[0057] The second photosensing unit 705b has a first surface 733 facing the reflective layer 719 and a second surface 701b opposite to the first surface 733.

[0058] Compared with the first surface 101a of the semiconductor device 701, by setting the first surface 733 of the second photosensing unit 705b to have roughness, since some light is refracted or reflected by the rough first surface 733 of the second photosensing unit 705b, less light is transmitted through the semiconductor device 701 to reach the second photosensing unit 705b. As a result, due to the rough first surface 733, less light reaches the second photosensing unit 705b, and less crosstalk interference is generated toward the adjacent first photosensing unit 703a. Therefore, the sensitivity of the adjacent first photosensing unit 703a is increased. It should be noted that the roughness of the first surface 733 of the second photosensing unit 705b is designed such that the reduction of light toward the second photosensing unit 705b due to the roughness of the first surface 733 does not affect the intended purpose of the second photosensing unit 705b, that is, receiving more radiation than the first photosensing unit 703a.

[0059] Figures 8A to 8H A method of manufacturing a semiconductor device such as the semiconductor devices of FIGS. 2(a), 2(b), 3(a) and 3(b) is shown.

[0060] Reference Figure 8A , provide or receive a substrate 801. The substrate 801 has a first surface 801a and a second surface 801b opposite to the first surface 801a. In some embodiments, the substrate 801 is a bulk semiconductor substrate (e.g., a bulk silicon (Si) substrate), a silicon-on-insulator (SOI) substrate, or a wafer. In some embodiments, the substrate 801 is a wafer.

[0061] The substrate 801 includes a plurality of first photosensing units 803a, 803b and a plurality of second photosensing units 805a, 805b arranged in a sub-array adjacent to the first surface 801a of the substrate 801. The first photosensing units 803a, 803b and the second photosensing units 805a, 805b are arranged such that at least a portion of the first photosensing unit 803a is adjacent to at least one first photosensing unit 803b. In some embodiments, the first photosensing units 803a, 803b are different from the second photosensing units 805a, 805b in that the surfaces of the second photosensing units 805a, 805b are rough.

[0062] Logic devices 823a, 823b such as transistors can be further disposed on a third surface 801c opposite to the first surface 101a of the substrate 801. The logic devices 823a, 823b are operable to ensure readings of the first photosensing units 803a, 803b, the second photosensing units 805a, 805b, or both. In some embodiments, the logic devices 823a, 823b are disposed adjacent to the first photosensing units 803a, 803b, the second photosensing units 805a, 805b, or both. In some embodiments, the logic devices 823a, 823b are disposed adjacent to the third surface 801c (opposite to the first surface 801a of the substrate 801) and near the back ends of the first photosensing units 803a, 803b and the second photosensing units 805a, 805b.

[0063] A circuit stack 829 can be further disposed adjacent to the logic devices 823a, 823b. The circuit stack 829 can be disposed adjacent to the second surface 801b of the substrate 801. In some embodiments, the circuit stack 829 is a back-end-of-line (BEOL) metallization stack. According to some embodiments, the circuit stack 829 is electrically connected to the logic devices 823a, 823b through at least one conductive via, at least one conductive contact, or a combination thereof. In some embodiments, the circuit stack 829 includes at least one metal layer 827 and at least one dielectric layer 825.

[0064] Still referring to Figure 8A , trenches 808c, 808b, 808a can be disposed between the first photosensing unit 803a and the second photosensing unit 805a, between the first photosensing unit 803a and the first photosensing unit 803b, and between the first photosensing unit 803b and the second photosensing unit 805b. In some embodiments, the trenches 808c, 808b, 808a have a substantially rectangular, trapezoidal, elongated oval, or any other suitable shape.

[0065] In some embodiments, the trenches 808c, 808b, 808a are formed by an etching technique, a drilling technique (e.g., mechanical or laser drilling technique), or any suitable technique applied from the first surface 801a of the substrate 801 towards the second surface 801b of the substrate 801.

[0066] Referring to Figure 8B , a pad 807 is disposed adjacent to the first surface 801a of the substrate 801. The pad 807 is disposed to be conformal to the shape of the trenches 808c, 808b, 808a of the substrate 801. In some embodiments, the pad 807 is formed by an atomic layer deposition (ALD) technique, a chemical vapor deposition (CVD) technique, or any suitable technique.

[0067] Reference Figure 8C Figure 8C The insulating structures 809a, 809b, 809c are arranged adjacent to the gasket 807. In some embodiments, the insulating structures 809a, 809b, 809c fill the trenches 808c, 808b, 808a of the substrate 801. In some embodiments, the insulating structures 809a, 809b, 809c are arranged by atomic layer deposition (ALD) technology, chemical vapor deposition (CVD) technology or any suitable technology.

[0068] Reference Figure 8D Figure 8D The first dielectric layer 813 is arranged adjacent to the gasket 807. In some embodiments, the first dielectric layer 813 is arranged on the gasket 807 and the insulating structures 809a, 809b, 809c. In some embodiments, the first dielectric layer 813 is arranged by atomic layer deposition (ALD) technology, chemical vapor deposition (CVD) technology or any suitable technology.

[0069] Reference Figure 8E Figure 8E The metal layers 815a, 815b, 815c are arranged adjacent to the first dielectric layer 813. In some embodiments, the metal layers 815a, 815b, 815c are arranged corresponding to parts of the first isolation structures 811a, 811b, 811c. In some embodiments, the metal layers 815a, 815b, 815c are formed by a technology selected from plating technology, lithography technology, polishing technology and etching technology.

[0070] Reference Figure 8F Figure 8F The second dielectric layer 817 is arranged adjacent to the first dielectric layer 813. In some embodiments, the second dielectric layer 817 is arranged on the metal layers 815a, 815b, 815c and the first dielectric layer 813. In some embodiments, the second dielectric layer 817 is arranged by atomic layer deposition (ALD) technology, chemical vapor deposition (CVD) technology or any suitable technology.

[0071] Reference Figure 8G Figure 8G The reflective layer 819 is arranged adjacent to the second dielectric layer 817. The reflective layer 819 is arranged at positions corresponding to the first photosensing units 803a, 803b, which defines the regions of the first photosensing units 803a, 803b. In some embodiments, the reflective layer 819 is arranged by a technology selected from plating technology, lithography technology, polishing technology and etching technology.

[0072] Reference Figure 8H, the third dielectric layer 821 is disposed adjacent to the second dielectric layer 817. In some embodiments, the third dielectric layer 821 is disposed above the reflective layer 819 and the second dielectric layer 817. In some embodiments, the third dielectric layer 821 is disposed by atomic layer deposition (ALD) technology, chemical vapor deposition (CVD) technology, or any suitable technology. Subsequently, a semiconductor device such as the one shown in FIGS. 2(b) and 3(b) is obtained.

[0073] In some embodiments, a dicing process is further performed on the semiconductor device obtained from the above process to obtain an image sensor including at least one pixel sensor, the pixel sensor including a first photosensing unit 803a and a second photosensing unit 805a arranged in a sub-array with the first photosensing unit 803a, wherein at least a part of the first photosensing unit 803a is adjacent to at least one first photosensing unit 803b of another pixel sensor.

[0074] Embodiments of the present application provide a semiconductor device, including: a plurality of first-type photosensing units, wherein each of the plurality of first-type photosensing units is operable to receive a first radiation amount; and a plurality of second-type photosensing units, wherein each of the plurality of second-type photosensing units is operable to receive a second radiation amount, and the plurality of second-type photosensing units and the plurality of first-type photosensing units are arranged in an array to form a pixel sensor, wherein the first radiation amount is less than the second radiation amount, and at least a part of a first example of the first-type photosensing units of the plurality of first-type photosensing units is adjacent to a second example of the first-type photosensing units of the plurality of first-type photosensing units.

[0075] In some embodiments, a first part of a first example of the first-type photosensing units is surrounded by a first second photosensing unit of the plurality of second-type photosensing units, and a second part of the first example of the first-type photosensing units is surrounded by a second example of the first-type photosensing units, and the first part is not greater than the second part.

[0076] In some embodiments, a first part of a first example of the first-type photosensing units is surrounded by a first photosensing unit of the plurality of second-type photosensing units, and a second part of the first example of the first-type photosensing units is surrounded by a second example of the first-type photosensing units, and the first part is not greater than the second part.

[0077] In some embodiments, the plurality of second-type photosensing units are circular regions surrounded by the plurality of first-type photosensing units.

[0078] In some embodiments, a reflective layer is further included above the plurality of first-type photosensing units.

[0079] In some embodiments, the reflective layer extends from the projection area of one of the plurality of first-type light sensing units to the projection area of one of the plurality of second-type light sensing units.

[0080] In some embodiments, it further includes: a first isolation structure located between one of the plurality of first-type light sensing units and one of the plurality of second-type light sensing units; and a second isolation structure located between adjacent first-type light sensing units of the plurality of first-type light sensing units, wherein the first isolation structure has a larger projection area than the second isolation structure.

[0081] In some embodiments, it further includes a third type of light sensing unit located between one of the plurality of first-type light sensing units and one of the plurality of second-type light sensing units, wherein the third type of light sensing unit is operable to receive less radiation compared to the first radiation amount or the second radiation amount.

[0082] Embodiments of the present application provide a semiconductor image sensor, including: a pixel sensor array, wherein the pixel sensor array includes a first pixel sensor and a second pixel sensor, and the first pixel sensor includes: a first type of light sensing unit; and a second type of light sensing unit, wherein the first type of light sensing unit and the second type of light sensing unit are arranged in a sub-array, wherein the first type of light sensing unit is operable to receive less radiation compared to the second type of light sensing unit, and at least a part of the first type of light sensing unit is adjacent to the second pixel sensor.

[0083] In some embodiments, a first part of the first type of light sensing unit is surrounded by a second type of light sensing unit, a second part of the first type of light sensing unit is surrounded by another first type of light sensing unit of another pixel sensor of the pixel sensor array, and the first part is not greater than the second part.

[0084] In some embodiments, a first example of the first type of light sensing unit is adjacent to a second example of the first type of light sensing unit at a first side, and is adjacent to a third example of the first type of light sensing unit at a second side adjacent to the first side.

[0085] In some embodiments, a first example of the first type of light sensing unit is adjacent to a second example of the first type of light sensing unit at a first side, and is adjacent to a third first type of light sensing unit at a second side adjacent to the first side.

[0086] In some embodiments, it further includes a reflective layer above the first type of light sensing unit.

[0087] In some embodiments, the reflective layer extends from the projection area of the first type of light sensing unit to the projection area of the second type of light sensing unit.

[0088] In some embodiments, the first type of light sensing unit is located at a corner of the first pixel sensor.

[0089] In some embodiments, it further includes: a first isolation structure located between the first type of light sensing unit and the second type of light sensing unit; and a second isolation structure located between adjacent first type of light sensing units, wherein the first isolation structure has a larger projection area than the second isolation structure.

[0090] In some embodiments, it further includes a third type of light sensing unit between the first type of light sensing unit and the second type of light sensing unit, wherein the third type of light sensing unit is operable to receive less radiation compared to the first type of light sensing unit or the second type of light sensing unit.

[0091] Embodiments of the present application provide a method for manufacturing a semiconductor device, including: disposing a plurality of first type of light sensing units on a substrate; disposing a plurality of second type of light sensing units arranged on the substrate, wherein each of the plurality of first type of light sensing units is operable to receive less radiation compared to each of the plurality of second type of light sensing units, and disposing the plurality of second type of light sensing units includes disposing at least one of the plurality of second type of light sensing units adjacent to a part of at least one of the plurality of first type of light sensing units; disposing a first isolation structure between one of the plurality of first type of light sensing units and one of the plurality of second type of light sensing units; disposing a second isolation structure between adjacent first type of light sensing units of the plurality of first type of light sensing units; and disposing a reflective layer on the plurality of first type of light sensing units.

[0092] In some embodiments, disposing the first isolation structure includes disposing the first isolation structure with a larger projection area than the second isolation structure.

[0093] In some embodiments, disposing the reflective layer includes disposing the reflective layer to extend from the projection area of the plurality of first type of light sensing units to the projection area of the plurality of second type of light sensing units.

[0094] In some embodiments, it further includes roughening the surface of at least one of the plurality of second type of light sensing units.

[0095] In some embodiments, it further includes arranging a third type of light sensing unit between at least one of the plurality of first type of light sensing units and at least one of the plurality of second type of light sensing units, wherein the third type of light sensing unit is operable to receive less radiation compared to each of the plurality of first type of light sensing units or each of the plurality of second type of light sensing units.

[0096] In some embodiments, a semiconductor device is provided. The semiconductor device includes a plurality of first light sensing units and a plurality of second light sensing units arranged in a sub-array with the first light sensing units, wherein the first light sensing units are light sensing units operable to receive less radiation compared to the second light sensing units, and at least a portion of the first light sensing units is adjacent to at least one first light sensing unit.

[0097] In some embodiments, a semiconductor image sensor is provided. The semiconductor image sensor includes a pixel sensor, which includes a first light sensing unit and a second light sensing unit arranged in a sub-array with the first light sensing unit, wherein the first light sensing unit is a light sensing unit operable to receive less light radiation compared to the second light sensing unit, and at least a portion of the first light sensing unit is adjacent to at least one first light sensing unit of another pixel sensor.

[0098] In some embodiments, a method of manufacturing a semiconductor device is provided. The method includes: providing a substrate having a first surface and a second surface opposite to the first surface; arranging a plurality of first light sensing units and a plurality of second light sensing units in a sub-array adjacent to the first surface of the substrate, wherein the first light sensing units are light sensing units operable to receive less radiation compared to the second light sensing units, and at least a portion of the first light sensing units is adjacent to at least one first light sensing unit; arranging a first isolation structure between the first light sensing units and the second light sensing units, and arranging a second isolation structure between adjacent first light sensing units; and disposing a reflective layer over the first light sensing units.

[0099] The features of several embodiments are outlined above so that those skilled in the art can better understand various aspects of the present invention. Those skilled in the art should understand that they can readily use the present invention as a basis to design or modify other processes and structures for implementing the same purposes and / or achieving the same advantages as the embodiments introduced herein. Those skilled in the art should also realize that such equivalent constructs do not depart from the spirit and scope of the present invention, and that they can make various changes, substitutions, and alterations herein without departing from the spirit and scope of the present invention.

Claims

1. A semiconductor device, comprising: a plurality of light sensing units of a first type, wherein each of the plurality of light sensing units of the first type is operable to receive a first amount of radiation; and a plurality of light sensing units of a second type, wherein each of the plurality of light sensing units of the second type is operable to receive a second amount of radiation, and the plurality of light sensing units of the second type and the plurality of light sensing units of the first type are arranged in an array to form a pixel sensor, a plurality of light sensing units of a third type, located between the plurality of light sensing units of the first type and the plurality of light sensing units of the second type, wherein, the first amount of radiation is less than the second amount of radiation, and at least a part of a first example of the plurality of light sensing units of the first type is adjacent to a second example of the plurality of light sensing units of the first type, wherein the first example of the plurality of light sensing units of the first type, the second example of the plurality of light sensing units of the second type, and the third example of the plurality of light sensing units of the third type constitute a pixel sensor, and the ratio of the projection area of the second example of the plurality of light sensing units of the second type to the first example of the plurality of light sensing units of the first type is 3:1, wherein the plurality of light sensing units of the first type are surrounded by the plurality of light sensing units of the second type and the plurality of light sensing units of the third type.

2. The semiconductor device according to claim 1, wherein, a first part of the first example of the plurality of light sensing units of the first type is surrounded by the third example of the plurality of light sensing units of the third type, and a second part of the first example of the plurality of light sensing units of the first type is surrounded by the second example of the plurality of light sensing units of the first type, and the first part is not greater than the second part.

3. The semiconductor device according to claim 1, wherein, The plurality of light sensing units of the first type is a circular area surrounded by the plurality of light sensing units of the third type.

4. The semiconductor device according to claim 1, further comprising a reflective layer above the plurality of light sensing units.

5. The semiconductor device according to claim 4, wherein The reflective layer extends from the projection area of one of the plurality of light sensing units of the first type to the projection area of one of the plurality of light sensing units of the second type.

6. The semiconductor device according to claim 1, further comprising: a first isolation structure, located between one of the plurality of light sensing units of the first type and one of the plurality of light sensing units of the third type; and a second isolation structure, located between adjacent light sensing units of the first type among the plurality of light sensing units of the first type, wherein the first isolation structure has a larger projection area than the second isolation structure.

7. The semiconductor device according to claim 1, wherein, Compared with the first amount of radiation or the second amount of radiation, the light sensing units of the third type are operable to receive less radiation.

8. A semiconductor image sensor, comprising: a pixel sensor array, wherein the pixel sensor array includes a first pixel sensor and a second pixel sensor, and the first pixel sensor includes: a first example of a light sensing unit of the first type; A second example of the second type of light sensing unit; and A third example of the third type of light sensing unit, wherein the first type of light sensing unit, the second type of light sensing unit, and the third type of light sensing unit are arranged in a sub-array, and the third type of light sensing unit is located between the first type of light sensing unit and the second type of light sensing unit, wherein Compared with the second type of light sensing unit, the first type of light sensing unit is operable to receive less radiation, and At least a part of the first type of light sensing unit is adjacent to the second pixel sensor, Wherein, the ratio of the projection area of the second example of the second type of light sensing unit to the first example of the first type of light sensing unit is 3:1, Wherein, the first type of light sensing unit is surrounded by the second type of light sensing unit and the third type of light sensing unit.

9. The semiconductor image sensor according to claim 8, wherein, A first part of the first example of the first type of light sensing unit is surrounded by the third type of light sensing unit, a second part of the first example of the first type of light sensing unit is surrounded by another first type of light sensing unit of another pixel sensor of the pixel sensor array, and the first part is not greater than the second part.

10. The semiconductor image sensor according to claim 8, wherein The first example of the first type of light sensing unit is adjacent to the second example of the first type of light sensing unit at a first side, and is adjacent to a third first type of light sensing unit at a second side adjacent to the first side.

11. The semiconductor image sensor according to claim 8, further comprising a reflective layer above the first type of light sensing unit.

12. The semiconductor image sensor according to claim 11, wherein, The reflective layer extends from the projection area of the first type of light sensing unit to the projection area of the second type of light sensing unit.

13. The semiconductor image sensor according to claim 8, wherein: The first type of light sensing unit is located at a corner of the first pixel sensor.

14. The semiconductor image sensor according to claim 8, further comprising: A first isolation structure located between the first type of light sensing unit and the third type of light sensing unit; And A second isolation structure located between adjacent first type of light sensing units, wherein the first isolation structure has a larger projection area than the second isolation structure.

15. The semiconductor image sensor according to claim 8, wherein, Compared with the first type of light sensing unit or the second type of light sensing unit, the third type of light sensing unit is operable to receive less radiation.

16. A method of manufacturing a semiconductor device, comprising: Providing a plurality of first type of light sensing units on a substrate; Providing a plurality of second type of light sensing units arranged on the substrate, Providing a plurality of light sensing units of a third type disposed on the substrate, wherein the light sensing units of the third type are located between the light sensing units of the first type and the light sensing units of the second type, and the plurality of light sensing units of the first type are surrounded by the plurality of light sensing units of the second type and the plurality of light sensing units of the third type, wherein each of the plurality of light sensing units of the first type is operable to receive less radiation compared to each of the plurality of light sensing units of the second type, and providing the plurality of light sensing units of the third type includes disposing at least one of the plurality of light sensing units of the third type adjacent to a portion of at least one of the plurality of light sensing units of the first type; Providing a first isolation structure between one of the plurality of light sensing units of the first type and one of the plurality of light sensing units of the third type; Providing a second isolation structure between adjacent light sensing units of the first type among the plurality of light sensing units of the first type; and Providing a reflective layer over the plurality of light sensing units of the first type, wherein a first example of the plurality of light sensing units of the first type, a second example of the plurality of light sensing units of the second type, and a third example of the plurality of light sensing units of the third type constitute a pixel sensor, and a ratio of a projection area of the second example of the plurality of light sensing units of the second type to a projection area of the first example of the light sensing units of the first type is 3:

1.

17. The method according to claim 16, wherein, Providing the first isolation structure includes providing the first isolation structure with a larger projection area than the second isolation structure.

18. The method according to claim 16, wherein, Providing the reflective layer includes providing the reflective layer to extend from a projection area of the plurality of light sensing units of the first type to a projection area of the plurality of light sensing units of the second type.

19. The method according to claim 16, further comprising roughening a surface of at least one of the plurality of light sensing units of the second type.

20. The method according to claim 16, wherein The light sensing units of the third type are operable to receive less radiation compared to each of the plurality of light sensing units of the first type or each of the plurality of light sensing units of the second type.

Images