Manufacturing method of through-type LTCC (Low Temperature Co-Fired Ceramic) step cavity

Abstract

The invention discloses a manufacturing method of a through-type LTCC step cavity, and the method comprises the steps: carrying out the cutting of a through groove on a plurality of green ceramic chips corresponding to each step, carrying out the lamination of the plurality of cut green ceramic chips, placing a plurality of green ceramic chips at the bottom of the (N-1) th step according to the height of the Nth step, and carrying out the lamination, the cavity plugs are sequentially plugged into the corresponding positions from bottom to top, and a to-be-laminated green ceramic body is obtained; placing the encapsulated to-be-laminated green ceramic body for lamination, and carrying out co-firing sintering on the green ceramic body with the cavity plug taken out; determining a running path of laser cutting; determining the power, the moving speed and the frequency of laser according to the characteristics and the cutting-up thickness of the sintered green ceramic body; and the laser cutting-up program is operated to complete machining of the Nth layer of step, and the through-type LTCC step cavity is obtained. According to the invention, the assembly distance between devices is reduced, and the packaging density and precision are greatly improved.

Description

Technical Field

[0001] The invention relates to a method for manufacturing a through-type LTCC step cavity, belonging to the technical field of semiconductor manufacturing. Background Art

[0002] Currently, the manufacturing method for LTCC (low temperature co-fired ceramic) cavities generally uses a filling method to complete lamination molding.

[0003] The existing cavity manufacturing method is only applicable to the production of conventional cavities, and has certain requirements for the cavity depth. When facing a cavity with a larger depth, the existing cavity manufacturing method cannot meet the flatness requirements of the cavity bottom. At the same time, the cavity processing accuracy is affected by the unstable sintering shrinkage rate of the green porcelain, and there is a risk of cavity delamination in severe cases.

[0004] Therefore, in view of the shortcomings of the existing technology, how to improve the manufacturing accuracy of LTCC cavities with complex shapes and steps and reduce the complexity of fillers and processes are technical problems that people in this field urgently need to solve. Summary of the invention

[0005] Purpose: In order to overcome the deficiencies in the prior art, the present invention provides a method for manufacturing a through-type LTCC step cavity, which is suitable for the manufacture of through-type step cavities in the production of various ceramic substrates and devices.

[0006] Technical solution: To solve the above technical problems, the technical solution adopted by the present invention is:

[0007] A method for manufacturing a through-type LTCC step cavity comprises the following steps:

[0008] Step 1: According to the LTCC design layout, determine the shape, size and relative position of the i-th step in the through-type LTCC step cavity, where i is an integer greater than or equal to 2.

[0009] Step 2: Decompose the cavity from top to bottom from the top surface of each step to obtain N steps, where N represents the total number of steps.

[0010] Step 3: Mill grooves on the template according to the shapes and sizes of the 1st to N-1th steps from top to bottom, pour the colloid into the grooves and solidify them into N-1 cavity plugs, and take out the N-1 cavity plugs for use.

[0011] Step 4: According to the shapes, sizes and relative positions of the 1st to N-1th steps, through grooves are cut on the multiple raw porcelain sheets corresponding to each step, and then the cut multiple raw porcelain sheets corresponding to each step are stacked according to the order of the 1st to N-1th steps. According to the height of the Nth step, multiple raw porcelain sheets are placed at the bottom of the N-1th step for stacking, and the cavity plugs corresponding to the 1st to N-1th steps are inserted into the corresponding positions from bottom to top in sequence to obtain the green porcelain body to be laminated.

[0012] Step 5: Place the green ceramic body to be laminated into a bag for vacuum packaging to obtain the encapsulated green ceramic body to be laminated.

[0013] Step 6: Place the encapsulated green ceramic body to be laminated for lamination to obtain a completed laminated green ceramic body.

[0014] Step 7: Unpack the laminated green ceramic body and take out N-1 cavity plugs in sequence to obtain a green ceramic body with the cavity plugs removed.

[0015] Step 8: co-sintering the green ceramic body with the cavity plug removed to obtain a sintered green ceramic body.

[0016] Step 9: Determine the laser scribing path based on the shape, size and relative position of the Nth step. Determine the laser power, moving speed and frequency based on the characteristics of the sintered green ceramic body and the scribing thickness.

[0017] Step 10: Run the laser scribing program to complete the processing of the Nth step layer to obtain a through-type LTCC step cavity.

[0018] As a preferred embodiment, the relative position of the i-th step is (x, y), wherein: x represents the distance between the width of the i-th step and the width of the green porcelain body, and y represents the distance between the length of the i-th step and the length of the green porcelain body.

[0019] As a preferred solution, the template is made of an alumina plate.

[0020] As a preferred solution, the colloid is prepared by mixing green glue and white glue in a volume ratio of 1:10.

[0021] As a preferred solution, the bag is an aluminum-plastic bag.

[0022] As a preferred solution, the lamination is performed using an isostatic laminator.

[0023] As a preferred solution, the co-firing sintering is performed in a co-firing furnace.

[0024] As a preferred solution, the parameters of the isostatic laminator are a pressure of 21 MPa, a holding temperature of 80° C., and a holding time of 10 min.

[0025] As a preferred solution, the parameters of the co-firing furnace are a sintering temperature of 850°C and a holding time of 10 minutes.

[0026] As a preferred solution, the laser power is 6 W, the moving speed is 1.4 mm / s and the frequency is 50 Hz.

[0027] Beneficial effects: The method for manufacturing a through-type LTCC step cavity provided by the present invention has the following advantages:

[0028] (1) Only a simple first-order cavity needs to be made, which is easy to operate and requires a lot of technical experience.

[0029] (2) There is no need to make complex-shaped step-shaped cavity plugs, thus eliminating the need to make complex cavity plug pouring molds, reducing costs.

[0030] (3) The first-order cavity has a simple shape, which makes the stress distribution uniform when the green porcelain body is pressed, reducing the occurrence of cavity deformation and stratification problems.

[0031] (4) First co-fire, then use laser cutting to keep the lower cavity as a whole during the co-fire process. This not only limits the deformation of the cavity, but also suppresses the warping of the step.

[0032] (5) Laser cutting has high precision and flexible cutting routes, so it is possible to produce complex and fine cavity shapes. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a schematic flow diagram of the processing method of the present invention.

[0034] Figure 2 It is a 3D schematic diagram of the 2-layer through-type LTCC step cavity of the present invention.

[0035] Figure 3 It is a plan view of a two-layer through-type LTCC step cavity of the present invention. Figure 3 (a) is a top view of the cavity. Figure 3 Middle (b) is a side cross-sectional view of the cavity.

[0036] Figure 4 It is a structural schematic diagram of the processing process of the present invention. DETAILED DESCRIPTION

[0037] The following is a clear and complete description of the technical solutions in the examples of the present invention in conjunction with the accompanying drawings in the examples of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the protection scope of the present invention.

[0038] The present invention will be further described below in conjunction with specific embodiments.

[0039] Embodiment 1:

[0040] like Figure 1 As shown, this embodiment introduces a method for manufacturing a through-type LTCC step cavity, including the following steps:

[0041] Step 1: Cavity confirmation: According to the LTCC design layout, determine the shape, size and relative position of the i-th step in the through-type LTCC step cavity, where i is an integer greater than or equal to 2.

[0042] Step 2: Decompose the cavity. Decompose the cavity from the top surface of each step from top to bottom to obtain N steps, where N represents the total number of steps.

[0043] Step 3: Make cavity plugs. Mill grooves on the template according to the shapes and sizes of the 1st to N-1th steps from top to bottom, then pour the colloid into the grooves to solidify and form N-1 cavity plugs, and take out N-1 cavity plugs for use.

[0044] Step 4: stacking the raw porcelain sheets. According to the shape, size and relative position of the 1st to N-1th steps, through grooves are cut on the multiple raw porcelain sheets corresponding to each step, and then the multiple raw porcelain sheets corresponding to each step are stacked according to the order of the 1st to N-1th steps. According to the height of the Nth step, multiple raw porcelain sheets are placed at the bottom of the N-1th step for stacking, and the cavity plugs corresponding to the 1st to N-1th steps are inserted into the corresponding positions from bottom to top in sequence to obtain the raw porcelain body to be laminated.

[0045] Step 5: Vacuum encapsulation: The green ceramic body to be laminated is placed in a bag for vacuum encapsulation to obtain the encapsulated green ceramic body to be laminated.

[0046] Step 6: Isostatic pressing and lamination: The encapsulated green ceramic body to be laminated is placed in the isostatic pressing and lamination is performed to obtain a laminated green ceramic body.

[0047] Step 7: Removing the cavity plugs. The laminated green ceramic body is unpacked, and N-1 cavity plugs are removed in sequence to obtain a green ceramic body with the cavity plugs removed.

[0048] Step 8: Co-firing and sintering. The green ceramic body with the cavity plug removed is co-fired and sintered to obtain a sintered green ceramic body.

[0049] Step 9: Confirm laser parameters. Determine the laser scribing path based on the shape, size and relative position of the Nth step. Determine the laser power, moving speed and frequency based on the characteristics of the sintered green ceramic body and the scribing thickness.

[0050] Step 10: Run the laser scribing program to complete the processing of the Nth step layer to obtain a through-type LTCC step cavity.

[0051] Further, in one embodiment, the relative position of the i-th step is (x, y), wherein: x represents the distance between the width of the i-th step and the width of the green porcelain body, and y represents the distance between the length of the i-th step and the length of the green porcelain body.

[0052] Furthermore, in one embodiment, the template is made of an aluminum oxide plate.

[0053] Furthermore, in one embodiment, the colloid is prepared by mixing green glue and white glue in a volume ratio of 1:10.

[0054] Furthermore, in one embodiment, the bag is an aluminum-plastic bag.

[0055] Furthermore, in one embodiment, the lamination is performed using an isostatic laminator.

[0056] Furthermore, in one embodiment, the co-firing is performed in a co-firing furnace.

[0057] Embodiment 2:

[0058] This embodiment introduces a method for manufacturing a through-type LTCC step cavity. Figure 2 As shown, taking N=2, a through-type LTCC step cavity consisting of 2 layers of steps as an example, the specific steps include:

[0059] Step 1: According to the LTCC design layout, determine the shape, size and relative position of the first and second steps in the through-type LTCC step cavity.

[0060] Furthermore, the shape of the first step is a rectangle, and the shape of the second step is a rectangle. The length, width, and height of the first step are l1×w1×h1, and the length, width, and height of the second step are l2×w2×h2. The relative position of the first step is (x1, y1), and the relative position of the first step is (x2, y2).

[0061] Among them, x1 represents the distance between the width of the first step and the width of the green porcelain body, and y1 represents the distance between the length of the first step and the length of the green porcelain body.

[0062] x2 represents the distance between the width of the second step and the width of the green porcelain body, and y2 represents the distance between the length of the second step and the length of the green porcelain body.

[0063] Step 2: Decompose the cavity from top to bottom from the top surface of each step to obtain two steps.

[0064] like Figure 4 As shown, step 3: according to the shape and size of the first step from top to bottom, grooves are milled on the template respectively, and then the colloid is poured into the groove to solidify and form a cavity plug, and a cavity plug is taken out for use.

[0065] Step 4: Lamination of raw ceramic sheets. According to the length and width of the rectangular shape of the first step and the relative position (x1, y1) of the first step, through grooves are cut on the multiple raw ceramic sheets corresponding to the first step. The total thickness of the multiple raw ceramic sheets corresponding to the first step is determined by the height of the rectangle of the first step.

[0066] The multiple raw ceramic sheets corresponding to the first step after cutting are stacked.

[0067] According to the height of the rectangle of the second step, multiple raw porcelain sheets are placed at the bottom of the first step for stacking, and the cavities corresponding to the first step are plugged into corresponding positions to obtain the raw porcelain body to be laminated.

[0068] Step 5: Place the green ceramic body to be laminated into a bag for vacuum packaging to obtain the encapsulated green ceramic body to be laminated.

[0069] Step 6: Place the encapsulated green ceramic body to be laminated for lamination to obtain a completed laminated green ceramic body.

[0070] Furthermore, the lamination is performed by an isostatic laminator, and the parameters of the isostatic laminator are a pressure of 21 MPa, a holding temperature of 80° C., and a holding time of 10 min.

[0071] Step 7: Unpack the laminated green porcelain body and take out one cavity plug to obtain a green porcelain body with the cavity plug removed.

[0072] Step 8: co-sintering the green ceramic body with the cavity plug removed to obtain a sintered green ceramic body.

[0073] Furthermore, the co-firing is performed in a co-firing furnace, and the parameters of the co-firing furnace are a sintering temperature of 850° C. and a holding time of 10 min.

[0074] Step 9: Confirm laser parameters. Determine the laser cutting path based on the shape, size and relative position of the second step.

[0075] Furthermore, the length, width and height of the rectangular shape of the second step, as well as the relative position (x2, y2) of the second step, determine the running path of the laser scribing.

[0076] The power, moving speed and frequency of the laser are determined according to the characteristics of the green ceramic body after sintering and the cutting thickness.

[0077] Furthermore, the LTCC cavity with a height of about 1 mm was processed using a laser power of 6 W, a moving speed of 1.4 mm / s, and a frequency of 50 Hz.

[0078] Step 10: Run the laser scribing program to complete the processing of the second step layer to obtain a through-type LTCC step cavity.

[0079] Since high-density, high-precision ceramic 3D packaging places higher requirements on the device assembly cavity, the relative position accuracy and dimensional accuracy of the cavity produced by this method are improved, which is conducive to reducing the assembly distance between devices and greatly improving the density and accuracy of the packaging. Compared with the conventional cavity production method, the position accuracy and dimensional accuracy of the cavity produced by laser scribing are effectively guaranteed.

[0080] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for manufacturing a through-type LTCC step cavity, characterized in that: The steps include: Step 1: According to the LTCC design layout, determine the shape, size and relative position of the i-th step in the through-type LTCC step cavity, where i is an integer greater than or equal to 2; Step 2: Decompose the cavity from top to bottom from the top surface of each step to obtain N steps, where N represents the total number of steps; Step 3: Mill grooves on the template according to the shapes and sizes of the 1st to N-1th steps from top to bottom, pour the colloid into the grooves and solidify them into N-1 cavity plugs, and take out the N-1 cavity plugs for use; Step 4: according to the shapes, sizes and relative positions of the 1st to N-1st steps, through grooves are cut on the multiple green porcelain sheets corresponding to each step, and then the multiple green porcelain sheets corresponding to each step are stacked according to the order of the 1st to N-1st steps, and according to the height of the Nth step, multiple green porcelain sheets are placed at the bottom of the N-1st step for stacking, and the cavity plugs corresponding to the 1st to N-1st steps are sequentially inserted into the corresponding positions from bottom to top to obtain the green porcelain body to be laminated; Step 5: placing the green ceramic body to be laminated into a bag for vacuum encapsulation to obtain the encapsulated green ceramic body to be laminated; Step 6: placing the encapsulated green ceramic body to be laminated for lamination to obtain a laminated green ceramic body; Step 7: unpacking the laminated green ceramic body and taking out N-1 cavity plugs in sequence to obtain a green ceramic body with the cavity plugs removed; Step 8: co-firing the green ceramic body with the cavity plug removed to obtain a sintered green ceramic body; Step 9: Determine the running path of the laser scribing according to the shape, size and relative position of the Nth step; determine the power, moving speed and frequency of the laser according to the characteristics of the sintered green ceramic body and the scribing thickness; Step 10: Run the laser scribing program to complete the processing of the Nth step layer to obtain a through-type LTCC step cavity.

2. The method for manufacturing a through-type LTCC step cavity according to claim 1, characterized in that: The relative position of the i-th step is (x, y), where x represents the distance between the width of the i-th step and the width of the green porcelain body, and y represents the distance between the length of the i-th step and the length of the green porcelain body.

3. The method for manufacturing a through-type LTCC step cavity according to claim 1, characterized in that: The template is an aluminum oxide plate.

4. The method for manufacturing a through-type LTCC step cavity according to claim 1, characterized in that: The colloid is prepared by mixing green glue and white glue in a volume ratio of 1:

10.

5. The method for manufacturing a through-type LTCC step cavity according to claim 1, characterized in that: The bag is an aluminum-plastic bag.

6. The method for manufacturing a through-type LTCC step cavity according to claim 1, characterized in that: The lamination is completed by using an isostatic laminator.

7. The method for manufacturing a through-type LTCC step cavity according to claim 1, characterized in that: The co-firing sintering is completed in a co-firing furnace.

8. The method for manufacturing a through-type LTCC step cavity according to claim 6, characterized in that: The parameters of the isostatic laminator are pressure 21 MPa, holding temperature 80°C and holding time 10 min.

9. The method for manufacturing a through-type LTCC step cavity according to claim 7, characterized in that: The parameters of the co-firing furnace are sintering temperature 850°C and holding time 10 min.

10. The method for manufacturing a through-type LTCC step cavity according to claim 1, characterized in that: The power of the laser was 6 W, the moving speed was 1.4 mm / s and the frequency was 50 Hz.

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