A method of manufacturing a semiconductor device

Abstract

The application provides a semiconductor device preparation method, comprising the following steps: S11, bonding a silicon base to a graphite carrier plate, and preparing an ILD layer after trench preparation, filling and planarization treatment; S12, etching the ILD layer to prepare a first hole section; S13, transferring the silicon base from the graphite carrier plate to a glass carrier plate through a cutting mold frame; S14, preparing a protective layer on the silicon base and the glass carrier plate; S15, etching and removing part of the protective layer, and reserving at least the protective layer in a contact hole; S16, etching along the first hole section to form a contact hole; S17, preparing a platinum silicon compound in the contact hole; and S18, preparing an aluminum block on the silicon base. The semiconductor device preparation method can firmly and reliably fix the silicon base to the glass carrier plate by using the protective layer, and does not need other bonding processes. Moreover, the protective layer reserved on the inner wall of the first hole section is beneficial to the preparation of the contact hole, and solves the problems of difficult contact hole alignment and difficult preparation of the contact hole between adjacent trenches with a small distance.

Description

Technical Field

[0001] This invention relates to the field of semiconductor device fabrication technology, and in particular to a method for fabricating a semiconductor device. Background Technology

[0002] In the fabrication of semiconductor devices, trenches and contact holes are involved. When the distance between trenches is small, it is difficult to create contact holes between adjacent trenches. Moreover, the fabrication of semiconductor devices involves the transfer and fixation of silicon substrates onto different carriers, and the operational processes for transferring and fixing silicon substrates onto different carriers need to be optimized. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to optimize the fabrication process of semiconductor devices. The present invention proposes a method for fabricating semiconductor devices.

[0004] A method for fabricating a semiconductor device according to an embodiment of the present invention includes: S11, Silicon-based bonding is performed to a graphite substrate, and the ILD layer is prepared after trench preparation, filling and planarization. S12, etch the ILD layer to prepare the first hole segment; S13, the silicon substrate is transferred from the graphite substrate to the glass substrate through a cutting mold frame; S14, a protective layer is prepared on the silicon substrate and the glass substrate; S15, etching away part of the protective layer, leaving at least the protective layer located within the contact hole; S16, Etch along the first hole segment to form a contact hole; S17, a platinum-silicon compound is prepared in the contact hole; S18, aluminum blocks are prepared on the silicon substrate.

[0005] According to some embodiments of the present invention, step S13 includes: S131, flip the silicon substrate and the graphite carrier so that the front side of the silicon substrate is placed in the cutting mold frame; S132, Debond the silicon substrate and the graphite carrier; S133, flip the cutting mold frame and the silicon substrate so that the back side of the silicon substrate is placed on the glass carrier plate; S134, Remove the cutting mold frame.

[0006] In some embodiments of the present invention, the protective layer in S14 is silicon oxynitride.

[0007] According to some embodiments of the present invention, in step S15, when etching the protective layer, a portion of the protective layer is reserved on the inner wall of the first hole segment to form a sidewall.

[0008] In some embodiments of the present invention, in step S16, the contact hole is prepared by etching along the first hole segment under the protection of the sidewall.

[0009] According to some embodiments of the present invention, in step S15, when etching the protective layer, the protective layer is reserved at the periphery of the silicon substrate and at the upper surface of the glass substrate.

[0010] In some embodiments of the present invention, in step S15, before etching the protective layer, a baffle is used to shield the periphery of the silicon substrate to protect the protective layer at the periphery of the silicon substrate during etching.

[0011] In some embodiments of the present invention, step S17 includes: S171, platinum metal is deposited on a silicon-based surface, and platinum metal reacts with silicon or polycrystalline silicon at the contact hole to form a platinum silicon compound; S172 uses aqua regia to remove platinum metal, except for the platinum-silicon compound at the contact holes.

[0012] According to some embodiments of the present invention, step S18 includes: S181, An aluminum layer is prepared on the surface of the silicon substrate; S182, aluminum blocks are prepared by etching according to a preset pattern.

[0013] The present invention has the following beneficial effects: According to the semiconductor device fabrication method of the present invention, a protective layer can be used to firmly and reliably fix the silicon substrate to a glass substrate without the need for other bonding processes. Moreover, the protective layer reserved on the inner wall of the first hole segment facilitates the fabrication of contact holes, solving the problems of difficulty in contact hole alignment and difficulty in fabricating contact holes between adjacent trenches with small distances. Attached Figure Description

[0014] Figure 1 This is a flowchart of a method for fabricating a semiconductor device according to an embodiment of the present invention; Figure 2 This is a schematic diagram illustrating the fabrication of an ILD layer after trench preparation, filling, and planarization of silicon-based bonding to a graphite substrate according to an embodiment of the present invention. Figure 3 A schematic diagram illustrating the fabrication of a first aperture segment by etching the ILD layer according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the flipping onto the cutting mold frame according to an embodiment of the present invention; Figure 5 This is a schematic diagram of the debonding of a graphite carrier and a silicon substrate according to an embodiment of the present invention; Figure 6 This is a schematic diagram of the flipping onto the glass carrier plate according to an embodiment of the present invention; Figure 7 This is a schematic diagram illustrating the removal of the cutting mold frame according to an embodiment of the present invention; Figure 8 This is a schematic diagram illustrating the preparation of the protective layer according to an embodiment of the present invention; Figure 9 This is a schematic diagram of the protective layer for the etched portion according to an embodiment of the present invention; Figure 10 This is a schematic diagram of the contact hole according to an embodiment of the present invention; Figure 11 This is a schematic diagram illustrating the preparation of a platinum metal layer according to an embodiment of the present invention; Figure 12 A schematic diagram of forming a platinum compound on the inner wall of a contact hole according to an embodiment of the present invention; Figure 13 This is a schematic diagram of the aluminum overlay layer according to an embodiment of the present invention; Figure 14 This is a schematic diagram illustrating the preparation of an aluminum block according to an embodiment of the present invention.

[0015] Figure label: Silicon-based 10, trench 110, ILD layer 120, contact hole 130, first hole segment 131, platinum metal 140, platinum-silicon compound 141, aluminum layer 150, aluminum block 151. Graphite carrier 20, adhesive 30, glass carrier 40, adsorption hole 410, protective layer 50, side wall 510, cutting mold frame 60. Detailed Implementation

[0016] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the present invention will be described in detail below with reference to the accompanying drawings and preferred embodiments.

[0017] The steps described in the specification and the flowcharts in the accompanying drawings of this invention are not necessarily to be strictly followed according to the step numbers; the execution order of the steps can be changed. Furthermore, certain steps can be omitted, multiple steps can be combined into one step, and / or one step can be broken down into multiple steps.

[0018] like Figure 1 As shown, a method for fabricating a semiconductor device according to an embodiment of the present invention includes: S11, the silicon substrate 10 is bonded to the graphite substrate 20, and the ILD layer 120 is prepared after the trench 110 is fabricated, filled, and planarized; as shown Figure 2 As shown, the silicon substrate 10 and the graphite substrate 20 can be bonded together using adhesive 30 before subsequent processes can be performed. S12, etch ILD layer 120 to prepare the first hole segment 131, as shown. Figure 3 As shown; S13, the silicon substrate 10 is transferred from the graphite substrate 20 to the glass substrate 40 through the cutting mold frame 60, as follows: Figures 4-7 As shown; According to some embodiments of the present invention, step S13 includes: S131, flip the silicon substrate 10 and the graphite carrier 20 so that the front side of the silicon substrate 10 is placed in the cutting mold frame 60, as shown. Figure 4 As shown; S132, unbonding silicon substrate 10 and graphite substrate 20, as follows Figure 5 As shown; S133, flip the cutting mold frame 60 and the silicon substrate 10 so that the back of the silicon substrate 10 is placed on the glass carrier plate 40, as shown. Figure 6 As shown; S134, Remove the cutting mold frame 60, as shown Figure 7 As shown.

[0019] S14, a protective layer 50 is prepared on the silicon substrate 10 and the glass carrier plate 40, such as Figure 8 As shown; in some embodiments of the present invention, the protective layer 50 may be made of silicon oxynitride with a different etch ratio than the ILD layer 120 in order to perform selective etching.

[0020] S15, etching away part of the protective layer 50, leaving at least the protective layer 50 within the contact hole 130, such as Figure 9 As shown; According to some embodiments of the present invention, such as Figure 9 As shown, in step S15, when etching the protective layer 50, a portion of the protective layer 50 is reserved on the inner wall of the first hole segment 131 to form a sidewall 510. Therefore, the contact hole 130 can be fabricated under the protection of the sidewall 510. When the contact hole 130 is fabricated between two closely spaced trenches 110, the problem of the contact hole 130 connecting to the trench 110 and affecting the device fabrication yield can be avoided.

[0021] According to some embodiments of the present invention, in step S15, when etching the protective layer 50, the protective layer 50 is reserved at the periphery of the silicon substrate 10 and at the lower surface of the glass carrier 40. For example... Figure 9 As shown, when etching the protective layer 50, not only can the protective layer 50 inside the adsorption hole 410 be retained, but also the protective layer 50 around the silicon substrate 10 and on the lower surface of the glass substrate 40 can be retained. Thus, the protective layer 50 can be used to firmly and reliably fix the silicon substrate 10 to the glass substrate 40, so as to facilitate subsequent processes of the silicon substrate 10.

[0022] In some embodiments of the present invention, in step S15, before etching the protective layer 50, a baffle is used to shield the periphery of the silicon substrate 10 so as to protect the protective layer 50 at the periphery of the silicon substrate 10 when etching the protective layer 50.

[0023] S16, etching along the first hole segment 131 to form a contact hole 130, such as Figure 10 As shown; In some embodiments of the present invention, in step S16, the contact hole 130 is etched along the first hole segment 131 under the protection of the sidewall 510. It should be noted that, since the sidewall 510 is prepared, and the etching ratio of the sidewall 510 is different from that of the silicon substrate 10, the sidewall 510 will play a good protective role when etching the contact hole 130, which can solve the problem of difficult alignment when preparing the contact hole 130.

[0024] S17, platinum silicon compound 141 is prepared in contact hole 130, such as Figure 11 and Figure 12 As shown; In some embodiments of the present invention, step S17 includes: S171, as Figure 11 As shown, platinum metal 140 is deposited on the surface of silicon substrate 10, and platinum metal 140 reacts with silicon or polycrystalline silicon at contact hole 130 to form platinum silicon compound 141; S172, as Figure 12 As shown, aqua regia is used to remove platinum metal 140, except for the platinum-silicon compound 141 at the contact hole 130.

[0025] S18, aluminum block 151 is prepared on silicon-based 10, such as Figure 13 and Figure 14 As shown.

[0026] According to some embodiments of the present invention, step S18 includes: S181, as Figure 13 As shown, an aluminum layer 150 is prepared on the surface of silicon-based 10; S182, as Figure 14 As shown, aluminum block 151 is prepared by etching according to a preset pattern.

[0027] According to the semiconductor device fabrication method of the present invention, the silicon substrate 10 can be firmly and reliably fixed to the glass substrate 40 using the protective layer 50 without the need for other bonding processes. Moreover, the protective layer 50 reserved on the inner wall of the first hole segment 131 facilitates the fabrication of the contact hole 130, solving the problems of difficulty in aligning the contact hole 130 and difficulty in fabricating the contact hole 130 between adjacent trenches 110 with small distances.

[0028] The method for fabricating a semiconductor device according to the present invention will now be described in detail with reference to the accompanying drawings and a specific embodiment. It is to be understood that the following description is merely exemplary and should not be construed as a specific limitation of the present invention.

[0029] like Figure 1 As shown, the method for fabricating a semiconductor device includes: S11, such as Figure 2 As shown, silicon substrate 10 is bonded to graphite substrate 20, and after the preparation, filling and planarization of trench 110 are completed, ILD layer 120 is prepared. S12, as Figure 3 As shown, the ILD layer 120 is etched to prepare the first hole segment 131; S13, as Figures 4-7 As shown, the silicon substrate 10 is transferred from the graphite substrate 20 to the glass substrate 40 via a cutting mold frame 60, specifically including: S131, as Figure 4 As shown, the silicon substrate 10 and the graphite carrier 20 are flipped so that the front side of the silicon substrate 10 is placed in the cutting mold frame 60. S132, as shown Figure 5 As shown, the silicon substrate 10 and the graphite substrate 20 are debonded; S133, such as Figure 6 As shown, the cutting mold frame 60 and silicon substrate 10 are flipped so that the back of silicon substrate 10 is placed on glass substrate 40; S134, such as Figure 7 As shown, remove the cutting mold frame 60.

[0030] S14, as Figure 8 As shown, a protective layer 50 is prepared on the silicon substrate 10 and the glass carrier 40. The protective layer 50 may be made of silicon oxynitride with a different etching ratio than that of the ILD layer 120 in order to perform selective etching.

[0031] S15, such as Figure 9 As shown, etching removes part of the protective layer 50, while retaining at least the protective layer 50 located within the contact hole 130; like Figure 9 As shown, in step S15, before etching the protective layer 50, a baffle is used to shield and protect the protective layer 50 around the silicon substrate 10. During etching of the protective layer 50, a portion of the protective layer 50 is reserved on the inner wall of the first hole segment 131 to form a sidewall 510. Therefore, the contact hole 130 can be fabricated under the protection of the sidewall 510. When the contact hole 130 is fabricated between two closely spaced trenches 110, the problem of the contact hole 130 connecting to the trench 110 and affecting the device fabrication yield can be avoided.

[0032] like Figure 9 In step S15, when etching the protective layer 50, not only the protective layer 50 inside the adsorption hole 410 can be retained, but also the protective layer 50 around the silicon substrate 10 and on the upper surface of the glass substrate 40 can be retained. Thus, the protective layer 50 can be used to firmly and reliably fix the silicon substrate 10 to the glass substrate 40, so as to facilitate subsequent processes of the silicon substrate 10.

[0033] S16, as Figure 10As shown, a contact hole 130 is formed by etching along the first hole segment 131; In step S16, under the protection of the sidewall 510, the contact hole 130 is etched along the first hole segment 131. It should be noted that, since the sidewall 510 is prepared, and the etching ratio of the sidewall 510 is different from that of the silicon substrate 10, the sidewall 510 will play a good protective role when etching the contact hole 130, which can solve the problem of alignment difficulties during the preparation of the contact hole 130.

[0034] S17, as shown Figure 11 and Figure 12 As shown, platinum silicon compound 141 is prepared in contact hole 130, specifically including: S171, as Figure 11 As shown, platinum metal 140 is deposited on the surface of silicon substrate 10, and platinum metal 140 reacts with silicon or polycrystalline silicon at contact hole 130 to form platinum silicon compound 141; S172, as Figure 12 As shown, aqua regia is used to remove platinum metal 140, except for the platinum-silicon compound 141 at the contact hole 130.

[0035] S18, such as Figure 13 and Figure 14 The process of fabricating aluminum block 151 on silicon-based 10 specifically includes: S181, as Figure 13 As shown, an aluminum layer 150 is prepared on the surface of silicon-based 10; S182, as Figure 14 As shown, aluminum block 151 is prepared by etching according to a preset pattern.

[0036] In summary, the semiconductor device fabrication method proposed in this invention can firmly and reliably fix the silicon substrate 10 to the glass substrate 40 using the protective layer 50, without the need for other bonding processes. Moreover, the protective layer 50 reserved on the inner wall of the first hole segment 131 facilitates the fabrication of the contact hole 130, solving the problems of difficulty in aligning the contact hole 130 and difficulty in fabricating the contact hole 130 between adjacent trenches 110 with small distances.

[0037] Through the description of specific embodiments, a more in-depth and specific understanding should be gained of the technical means and effects adopted by the present invention to achieve the intended purpose. However, the accompanying drawings are only provided for reference and illustration and are not intended to limit the present invention.

Claims

1. A method for fabricating a semiconductor device, characterized in that, include: S11, Silicon-based bonding is performed to a graphite substrate, and the ILD layer is prepared after trench preparation, filling and planarization. S12, etch the ILD layer to prepare the first hole segment; S13, the silicon substrate is transferred from the graphite substrate to the glass substrate through a cutting mold frame; S14, a protective layer is prepared on the surface of the silicon substrate and the glass carrier plate; S15, etching away part of the protective layer; when etching the protective layer, reserving part of the protective layer on the inner wall of the first hole segment to form a sidewall; and when etching the protective layer, reserving the protective layer at the periphery of the silicon substrate and the lower surface of the glass substrate. S16, under the protection of the sidewall, a contact hole is etched along the first hole segment; S17, Platinum metal is deposited on the silicon-based surface, and the platinum metal reacts with the silicon or polycrystalline silicon at the contact hole to form a platinum silicon compound; Aqua regia was used to remove platinum metal, except for the platinum-silicon compound at the contact holes; S18, an aluminum layer is prepared on the surface of the silicon substrate; Aluminum blocks are prepared by etching according to a preset pattern.

2. The method for fabricating a semiconductor device according to claim 1, characterized in that, Step S13 includes: S131, flip the silicon substrate and the graphite carrier so that the front side of the silicon substrate is placed in the cutting mold frame; S132, Debond the silicon substrate and the graphite carrier; S133, flip the cutting mold frame and the silicon substrate so that the back side of the silicon substrate is placed on the glass carrier plate; S134, Remove the cutting mold frame.

3. The method for fabricating a semiconductor device according to claim 1, characterized in that, The protective layer in S14 is silicon oxynitride.

4. The method for fabricating a semiconductor device according to claim 1, characterized in that, In step S15, before etching the protective layer, a baffle is used to shield the periphery of the silicon substrate to protect the protective layer at the periphery of the silicon substrate during etching.

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