TWI305047B - Image sensor and the method for manufacturing the same - Google Patents

Description

1305047, 屮:: refractive index of the dielectric layer 112 and the intermetal dielectric layers 114, 116, 118... (1) greater than the refractive index h of the optical barrier layer 12A. The optical barrier layer may be made of titanium oxide (titanium 〇xide), oxidized oxide or other material having a refractive index value consistent with the above requirements. In addition, considering that the metal itself has good optical reflection characteristics, the optical barrier layer 124 can also be replaced by a metal barrier layer to enhance the barrier effect of the optical barrier layer 124. ^ As shown in FIG. 7, a touch etching process is performed to remove the optical barrier layer 124 deposited on the surface of the intermetal dielectric layer 118 and the optical barrier layer 124 deposited on the concave bottom surface 122, leaving only the deposition A portion of the optical barrier layer 124 of the inner sidewall surface of the recess 12〇. Then, as shown in FIG. 8, a deposition process such as spin coating (SOG), chemical vapor deposition (CVD) process, thermal deposition process, and plasma enhanced chemical vapor deposition (PECVD) are performed. A process or physical vapor deposition (PVD) process or the like forms a filling layer 126 on the surface of the inter-metal dielectric layer us and the optical barrier layer 124 and fills the recess 120. In the preferred embodiment, the filling layer 126 can be made of a dichroic film material such as titanium oxide or tantalum oxide, and the filling layer 126 is not limited to color separation. For the production of a film material, it can also be made into a color filter layer by using a material of a color filter, such as a resin containing a color dye, a color resist or other inorganic compound, or using other transparent materials for light to pass through. It is the material of the filling layer 126. 1305047 ο (丨 (as shown in Fig. 9 'to conduct a chemical mechanical polishing planarization process to remove a portion of the filling layer 126 formed on the surface of the intermetal dielectric layer 18' to make the surface of the filling layer 126 and the metal The dielectric surface is flush; at this point, the recess 120, the optical barrier layer 124, and the fill layer 126 collectively form the waveguide 125 of the present invention. It is noted that in the preferred embodiment, the fill layer 126 There is a refractive index n2, and the refractive index n2 of the filling layer 126 is greater than the refractive index n3 of the optical barrier layer 124. Therefore, when an incident light is incident on the optical barrier layer 124, since the refractive index 填充 of the filling layer 126 is larger than the optical barrier layer The reflection coefficient of 124 is n3, so the incident light that is not normally incident will be totally reflected on the surface of the optical barrier layer 124 and then reach the optical element 106 to form a wave guide effect without crossing the inter-metal dielectric layer 114. , 116, 118 and the interlayer dielectric layer 112, causing a problem of spanning phenomenon. ^ As shown in FIG. 10, a flat layer 128 and a micro-convex can be formed over the inter-metal dielectric layer 118 and the waveguide 125. Microlens 130. The flat layer 128 protects the underlying inter-metal dielectric layers 114, 116, 118, the interlayer dielectric layer 112 and the waveguide 125 and forms a flat surface, which facilitates the subsequent process of forming the micro-concentrating mirror 130. The layer 128 can be a transparent film layer, such as a yttria layer, a transparent resin, glass, or other material having light transmissive properties, and the micro concentrator 130 can be formed on the flat layer 128 by forming a patterned polymer. The polymer is formed into a 16 1305047 via a tempering process

The concave bottom surface is spaced apart from the optical element 204 by a predetermined distance. In the present embodiment, the predetermined distance is about the thickness of the interlayer dielectric layer 208 to ensure the reliability of the optical element 204. The image sensing device 200 further includes a flat layer 220 and at least one micro condensing mirror 222 disposed above the dielectric layer 216 and the waveguide 215 to protect the lower dielectric layer 216 from the waveguide 215 and provide a concentrating effect. It should be noted that the sidewall of the waveguide 215 has a flat surface, so that when external light is incident, it is less likely to cause non-directional scattering. In the preferred embodiment, the interlayer dielectric layer 208 and the inter-metal dielectric layer are interposed. The electrical layers 210, 212, 214 each have the same refractive index η!, and the optical barrier layer 224 has a refractive index η3, wherein the refractive index η of the interlayer dielectric layer 208 and the intermetal dielectric layers 210, 212, 214! Greater than the refractive index η3 of the optical barrier layer 224, due to the difference in refractive index, the light 229 from the outside through the inter-metal dielectric layer 214 to the optical barrier layer 224 will be between the optical barrier layer 224 and the inter-metal dielectric layer 214. The interface reflection, the filling layer 226 may have a refractive index η2, and the refractive index η2 of the filling layer 226 is greater than the refractive index η3 of the optical barrier layer 224; therefore, when a light ray 228 is incident on the optical barrier layer 224, due to the filling layer 226 The refractive index η2 is greater than the refractive index η3 of the optical barrier layer 224, so that the ray 228 is totally reflected on the surface of the optical barrier layer 224 without the problem of traversing the dielectric layer 216 and causing a spanning phenomenon. In addition, considering that the metal itself can cause good light reflection effect and light is not easy to pass through, the optical barrier layer 224 can also be replaced by a metal barrier layer to strengthen 18 i^U5〇47

X. Patent application: I. An image sensing device comprising: a substrate comprising at least one optical component; at least one dielectric layer disposed on the substrate and the dielectric layer having a refractive index ηι; at least one a wave-guide tube disposed in the dielectric layer, the sidewall of the waveguide having a flat surface and the waveguide is corresponding to the optical element and spaced apart from the optical element by a predetermined distance, and the waveguide The method includes: a filling layer embedded in the dielectric layer, the filling layer has a refractive index n2; and an optical barrier layer disposed on a sidewall of the filling layer, the optical barrier layer has a refractive index n3, and the filling The refractive index of the layer is greater than the refractive index n3 of the optical barrier layer. W2. The image sensing device of claim 1, wherein the waveguide has a concave bottom surface. 3. The image sensing device of claim 1, wherein the dielectric layer comprises at least one interlayer dielectric layer, and at least one inter-metal dielectric layer is disposed over the interlayer dielectric layer. The image sensing device of claim 3 wherein the predetermined distance is the thickness of the interlayer dielectric layer. The image sensing device of claim 1, wherein the refractive index h of the dielectric layer is greater than the refractive index h of the optical barrier layer. The image sensing device of claim 1, wherein the filling layer is a color film. 7. The image sensing device of claim 1, wherein the fill layer is a color filter layer. 8. The image sensing device of claim 1, further comprising a micro condenser (micr〇lens) disposed above the waveguide. 9. The image sensing device of claim 1, wherein the optical component is a photosensitive diode. 10. The image sensing device of claim 1, wherein the image sensing device is a complementary MOS transistor image sensor. A method for fabricating an image sensing device, comprising: providing a substrate having at least one optical component; forming at least one dielectric layer on the substrate and covering the optical component; forming a dielectric layer in the dielectric layer a groove corresponding to the optical element 'and the groove is spaced apart from the optical element by a predetermined distance; 23, the inner sidewall surface of the groove forms a flat wire barrier layer; and a filling layer is formed Filling the groove to form a waveguide; wherein the layer has a refractive index n!, the filling layer has a refractive index n2, and the wire barrier layer has a refractive index 〜, and the refractive layer of the filling layer The coefficient n2 is greater than the refractive index n3 of the optical barrier layer. The method of fabricating claim 11, wherein the dielectric layer comprises at least one interlayer dielectric layer and at least one intermetal dielectric layer is disposed over the interlayer dielectric layer. 3' wherein the method of fabricating the item 12, wherein the predetermined distance is the thickness of the interlayer dielectric layer. W 1 (such as the manufacturing method of the request item u, wherein the groove has a concave bottom surface. The method for manufacturing the optical barrier layer on the inner sidewall surface of the groove comprises: a deposition process, forming an optical barrier layer on the surface of the dielectric layer, the inner sidewall of the recess, and the surface of the concave bottom surface; and forming a portion of the optical barrier layer on the bottom surface of the recessed surface And a portion of the surface of the dielectric layer of the optical barrier layer. 24: the square: = as a method of '47' forming the filling layer to fill the groove 1 product 5 to form a transfer layer on the surface of the layer Fill up

And the flattening process removes a portion of the filling layer deposited on the surface of the dielectric layer such that the surface of the filling layer is flush with the surface of the dielectric layer. Included in the method of forming a micro-concentrating mirror, which is greater than the refractive index of the optical barrier layer, wherein the refractive index of the dielectric layer is greater than the refractive index of the optical barrier layer. 〇 3. 19. An image sensing device, comprising: a substrate comprising at least one optical component; at least one dielectric layer disposed on the substrate; at least one wave-guide tube disposed in the dielectric layer The side wall of the waveguide has a flat surface and the waveguide corresponds to the optical element and is spaced a predetermined distance from the optical element, and the waveguide comprises: a filter layer embedded in the dielectric layer; A metal barrier layer is disposed on a sidewall of the filter layer. The image sensing device of claim 19, wherein the dielectric layer comprises at least one interlayer dielectric layer, and at least one inter-metal dielectric layer is disposed over the interlayer dielectric layer. 21. The image sensing device of claim 20, wherein the predetermined distance is a thickness of the interlayer dielectric layer. The image sensing device of claim 19, wherein the waveguide has a concave bottom surface. The image sensing device of claim 19, wherein the filter layer is a color separation film. 24. The image sensing device of claim 19, further comprising a micro concentrating mirror disposed above the waveguide. 25. The image sensing device of claim 19, wherein the optical component is a photodiode. 6. The image sensing device of claim 19, wherein the image sensing device is a complementary MOS transistor image sensor. A method for fabricating an image sensing device, the method comprising: providing a substrate having at least one optical component; forming at least one dielectric layer on the substrate and covering the optical component; forming a dielectric layer in the dielectric layer a groove corresponding to the optical element, wherein the groove is spaced apart from the optical element by a predetermined distance; a flat metal barrier layer is formed on the inner sidewall surface of the groove; forming a calender layer to fill The groove forms a waveguide. 28. The method of claim 27, wherein the dielectric layer comprises at least one interlayer dielectric layer' and at least an inter-metal dielectric layer disposed over the interlayer dielectric layer. 29. The method of claim 28, wherein the distance is the thickness of the interlayer dielectric layer. 30. The method of claim 27, wherein the groove has a concave bottom surface. ^T still 内 之 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内 内Forming, barrier enthalpy-etching process, etching deposition screen _ and the surface of the dielectric layer part 2 = gold 2 · _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ The method includes: performing a deposition process to form the filter layer on a surface of the dielectric layer and filling the recess;

A planarization process is performed to remove a portion of the light-receiving layer deposited on the surface of the dielectric layer such that the surface of the filter layer is flush with the surface of the dielectric layer. 33. The method of claim 32, wherein the planarizing process further comprises a process of forming a micro-concentrating mirror over the waveguide.

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