Packaging auxiliary device for improving cavity surface damage during semiconductor chip sintering
By designing a packaging auxiliary device including a ceramic backplane cleaning tank, the problem of cavity surface damage during semiconductor chip sintering is solved, and a higher sintering yield and the service life of the ceramic backplane are achieved.
Patent Information
- Application Number
- CN202421560124.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-03
- Publication Date
- 2025-05-16
- Estimated Expiration
- 2034-07-03
AI Technical Summary
During the sintering of semiconductor chips, the ceramic backplate, ceramic particles and chip cavity surface contact each other, resulting in point losses in the chip cavity surface, reducing the sintering yield and affecting the light output and service life of the chip.
A packaging auxiliary device is designed, including a fixture base plate and a fixture upper cover. A multiple ceramic back plate cleaning tank is arranged in the inner array of the top cover of the fixture upper cover. Each cleaning tank is vertically arranged inside the cleaning tank. The semiconductor chip cavity surface is adhered to the top surface of the ceramic back plate for sintering. Ceramic particles will not remain on the ceramic back plate during the sintering process, but flow into the cleaning tank.
It effectively avoids contact between the ceramic back plate, ceramic particles and chip cavity surface, reduces point losses on the chip cavity surface, improves the sintering yield, and extends the service life of the ceramic back plate.
Smart Images
Figure CN222884085U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of semiconductor chip packaging, in particular to a packaging auxiliary device for improving cavity surface damage during sintering of semiconductor chips. Background Art
[0002] Aluminum nitride ceramics are widely used in the high-power semiconductor laser packaging industry due to their excellent performance; the current bottom gold-plated ceramics generally have the phenomenon of ceramic particles falling off after cutting and decomposition; in order to ensure the horizontality of the high-power laser cavity surface, it is necessary to use un-gold-plated aluminum nitride with a surface roughness of 0.1-0.3μm as the backplane, and adopt the sintering alignment method with the chip cavity surface facing the ceramic backplane. In this process, the gold-plated ceramic particles at the bottom of the unit junction fall off and adhere to the ceramic backplane. The subsequent placement of the chip and alignment can easily cause damage to the cavity surface, reducing the sintering yield and affecting the chip's light output and service life.
[0003] Under the existing technical conditions, the main steps of unit junction sintering are negative electrode sintering and unit junction sintering. Among them, the un-gold-plated ceramic of the negative electrode is welded to the electrode surface. During the welding process, the gold-plated ceramic itself expands due to heat, and it is easy to produce μm-level ceramic particles. During the subsequent unit junction sintering, the negative electrode is first placed on the ceramic back plate. The clamping and placement of this process will cause the gold-plated ceramic particles to fall off and adhere to the surface of the ceramic back plate. When the chip is placed, the cavity surface faces the ceramic back plate. At this time, the ceramic back plate, ceramic particles and the chip cavity surface are in contact with each other, and the chip cavity surface is prone to point damage, which causes damage to the chip and makes it difficult to use. Utility Model Content
[0004] The embodiment of the utility model provides a packaging auxiliary device for improving cavity surface damage during sintering of semiconductor chips, which can solve the problem in the prior art that the ceramic back plate, ceramic particles and chip cavity surface are in contact with each other, and the chip cavity surface is prone to point damage, causing damage to the chip and making it difficult to use.
[0005] The present invention provides a packaging auxiliary device for improving the cavity surface damage during the sintering of semiconductor chips, comprising a jig bottom plate, a jig cover is fixed on the top of the jig bottom plate, a plurality of ceramic back plate cleaning grooves are arranged vertically in an array on the inner side of the top of the jig cover, and a ceramic back plate is arranged vertically inside each of the ceramic back plate cleaning grooves;
[0006] The top of each ceramic back plate supports the semiconductor chip together, and one side of the semiconductor chip contacts the ceramic back plate.
[0007] Preferably, two parallel strip-shaped clamping holes are arranged on the inner side of the upper cover of the fixture.
[0008] Preferably, the semiconductor chip comprises an electrode, a gold-plated ceramic is disposed on one side of the electrode, the chip is disposed on the other side of the electrode, and the gold-plated ceramic is adjacent to the chip.
[0009] Preferably, a plurality of screw holes are provided on the jig upper cover, and the jig upper cover and the jig bottom plate can be locked by screwing the screws into the screw holes.
[0010] Preferably, a plurality of drain grooves are provided on the side of the jig bottom plate, and the drain grooves are communicated with the inner side of the jig upper cover and the ceramic back plate cleaning groove.
[0011] Preferably, the interior of the ceramic back plate cleaning tank is provided with a chamfer, and the opening size of the ceramic back plate cleaning tank is larger than the vertical size of the ceramic back plate.
[0012] Preferably, the jig upper cover and the jig bottom plate are both made of polytetrafluoroethylene plates.
[0013] Preferably, when the cavity surface of the semiconductor chip is bonded to the top surface of the ceramic back plate and sintered for 8 to 10 times, the ceramic back plate is replaced.
[0014] The present invention provides a packaging auxiliary device for improving cavity surface damage during sintering of semiconductor chips. Compared with the prior art, the invention has the following beneficial effects:
[0015] The utility model vertically arranges a plurality of ceramic back plate cleaning grooves in an array on the inner side of the top of the jig upper cover, and vertically arranges a ceramic back plate inside each ceramic back plate cleaning groove. When the semiconductor chip is sintered, the cavity surface of the semiconductor chip is attached to the top surface of the ceramic back plate for sintering. Ceramic particles generated on the semiconductor chip during sintering will not remain on the ceramic back plate, but flow into the ceramic back plate cleaning groove along the side of the ceramic back plate. Therefore, it is not easy for the ceramic back plate, ceramic particles and the chip cavity surface to contact each other, and the chip cavity surface is not easy to have point damage, which will not cause damage to the chip, thereby improving the sintering qualification rate.
[0016] In addition, after each batch of semiconductor chips is sintered, the ceramic back plate can be cleaned by the alcohol in the ceramic back plate cleaning tank so that the ceramic particles and alcohol are mixed and flow out from the drain tank, which greatly improves the service life of the ceramic back plate. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure 1 A schematic diagram of the structure of a packaging auxiliary device for improving cavity surface damage during sintering of a semiconductor chip provided by an embodiment of the utility model;
[0018] Figure 2 A schematic diagram of a ceramic back plate of a packaging auxiliary device for improving cavity surface damage during sintering of a semiconductor chip provided by an embodiment of the utility model when the device is placed;
[0019] Figure 3 A schematic diagram of the unit structure of a packaging auxiliary device for improving cavity surface damage during sintering of a semiconductor chip provided by an embodiment of the utility model;
[0020] Figure 4 A schematic diagram of the working process of a packaging auxiliary device for improving cavity surface damage during sintering of a semiconductor chip provided by an embodiment of the utility model.
[0021] Among them: 1. Electrode, 2. Gold-plated ceramic, 3. Chip, 4. Fixture cover, 5. Fixture bottom plate, 6. Strip clamping hole, 7. Ceramic back plate cleaning slot, 8. Screw hole, 9. Drain slot, 10. Ceramic back plate. DETAILED DESCRIPTION
[0022] In order to make the above-mentioned purposes, features and advantages of the utility model more obvious and easy to understand, the specific implementation methods of the utility model are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the utility model. However, the utility model can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the utility model, so the utility model is not limited by the specific embodiments disclosed below.
[0023] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.
[0024] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present utility model, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.
[0025] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.
[0026] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.
[0027] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.
[0028] See also Figure 1 to Figure 3 The embodiment of the utility model provides a packaging auxiliary device for improving cavity surface damage during sintering of a semiconductor chip, including an electrode 1, a gold-plated ceramic 2, a chip 3, a fixture cover 4, a fixture bottom plate 5, a strip clamping hole 6, a ceramic back plate cleaning groove 7, a screw hole 8, a drain groove 9 and a ceramic back plate 10.
[0029] Among them, the jig cover 4 is made of polytetrafluoroethylene, which has good insulation, is relatively soft and corrosion-resistant; the jig bottom plate 5 is made of polytetrafluoroethylene, which has good insulation, is relatively soft and corrosion-resistant; the strip clamping hole 6 is convenient for clamping the jig in the solution to avoid direct contact between personnel and the cleaning solution; the ceramic back plate cleaning groove 7, the size of the cleaning groove is slightly larger than the ceramic back plate 10 and has chamfers and retains a certain distance from each other to avoid damage; the screw hole 8 is an M2.5*8 screw hole, which is used to fix the jig cover 4 and the jig bottom plate 5; the drain groove 9, when the jig is placed in the solution, the internal bubbles can be quickly removed, and when the nitrogen is blown directly from the top, the airflow drives the alcohol and particulate matter to be discharged from the drain groove 9.
[0030] The specific workflow is as follows: Figure 4 As shown, assemble the fixture as shown in Figure 1 After the jig cover 4 and the jig bottom plate 5 are completely fitted together, tighten them with M2.5*8 screws; put the ceramic back plate 10 into the jig, and use soft tweezers to pick up the ceramic back plate 10 and put it into the jig; ultrasonic cleaning, such as Figure 2 As shown, put the ceramic sheet and the fixture into the ultrasonic cleaning machine, pour alcohol to cover the ceramic back plate 10 by about 2-3cm, and clean for 10-15min; blow dry with nitrogen, and dry the surface alcohol with nitrogen after cleaning, and store it in a drying cabinet; use rubber gas to remove dust, and use rubber gas to remove dust on both sides of the ceramic back plate 10 before sintering; unit junction sintering, and perform unit junction sintering after the above steps are completed; the ceramic back plate 10 needs to be replaced periodically, and the replacement cycle of the ceramic back plate 10 should be controlled to be replaced every 8 to 10 furnaces. After the ceramic back plate 10 is replaced, restart cleaning and put it into use.
[0031] Specifically:
[0032] Use 12 M2.5*8 screws to lock the jig cover 4 and the jig bottom plate 5, and then use soft tweezers to clamp the ceramic back plate 10 and put it into the jig. Avoid bumping and producing new ceramic particles during the clamping process. After all the ceramic back plates 10 to be cleaned are put into the jig, put them into the ultrasonic cleaning machine and add 99.99% purity alcohol to cover the ceramic back plate 10 by about 2-3cm. The frequency of the ultrasonic cleaning machine must be 28-40KHZ, the power is 180-240W (experiments have shown that the cleaning effect is best within this range), and the cleaning time is 10-15min (avoid excessively high solution temperature). After 10-15min, use a clamp to extend into the clamping hole, take out the jig with the ceramic back plate 10, place it on the workbench, and use nitrogen (pressure <0.2MPa) to blow the ceramic back plate 10 and the jig directly from the top (the airflow drives the alcohol and particulate matter to be discharged from the drain tank 9). The surface of the ceramic back plate 10 and the alcohol inside the jig are It can be completely evaporated, so as to avoid residual alcohol affecting the welding effect of the unit junction; during sintering, personnel use soft tweezers to directly clamp the ceramic back plate 10 from the fixture (reduce the number of turnovers, avoid bumps and secondary pollution), and use a rubber air blower to tilt 45° to remove dust on both sides of the ceramic back plate 10 (remove small surface pollutants); after dust removal, place the ceramic back plate on the sintering fixture, place the chips in order normally, and use a cotton swab to align and sinter; replace the ceramic back plate 10 every 8 to 10 furnaces of sintering, put the replaced ceramic back plate 10 back into the fixture and clean it according to the above process, and it can be put into use again after cleaning; this design can effectively improve the chip cavity surface damage problem caused by the shedding of gold-plated ceramic substrate particles during sintering, while increasing the service life of the ceramic back plate 10 and the product, reducing the frequency of personnel using high-power microscopes to inspect the chip cavity surface, and significantly improving the efficiency of chip cavity surface inspection after sintering.
[0033] The technical solution designed by the utility model reduces the number of point losses on the chip cavity surface and improves the sintering yield by controlling the ceramic particles attached to the ceramic back plate 10 without changing the existing sintering process; the utility model has obvious improvements in the cleaning effect and efficiency of the ceramic back plate 10, and will not cause mechanical damage to the ceramic back plate 10, thereby increasing the service life of the ceramic back plate 10; the utility model can reduce the frequency of personnel using high-power microscopes to inspect the chip cavity surface and improve the inspection efficiency; the ceramic back plate 10 designed by the utility model can be reused after cleaning, reducing the scrap frequency of the ceramic back plate 10; the utility model has obvious improvements in the cleanliness of the chip cavity surface.
[0034] The above-mentioned embodiments only express several implementation methods of the utility model, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the utility model patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, which all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model patent shall be based on the attached claims.
Claims
1. A packaging auxiliary device for improving cavity surface damage during sintering of semiconductor chips, characterized in that: include: A jig bottom plate (5), a jig upper cover (4) being fixed on the top of the jig bottom plate (5), a plurality of ceramic back plate cleaning grooves (7) being arranged vertically in an array on the inner side of the top of the jig upper cover (4), and a ceramic back plate (10) being arranged vertically inside each of the ceramic back plate cleaning grooves (7); The top of each ceramic back plate (10) jointly supports the semiconductor chip, and one side of the chip (3) of the semiconductor chip contacts the ceramic back plate (10).
2. The packaging auxiliary device for improving cavity surface damage during sintering of semiconductor chips according to claim 1, characterized in that: Two parallel strip-shaped clamping holes (6) are arranged on the inner side of the jig upper cover (4).
3. The packaging auxiliary device for improving cavity surface damage during sintering of semiconductor chips according to claim 1, characterized in that: The semiconductor chip comprises an electrode (1), a gold-plated ceramic (2) is arranged on one side of the electrode (1), the chip (3) is arranged on the other side of the electrode (1), and the gold-plated ceramic (2) is adjacent to the chip (3).
4. The packaging auxiliary device for improving cavity surface damage during sintering of semiconductor chips according to claim 1, characterized in that: The jig upper cover (4) is provided with a plurality of screw holes (8), and after screws are screwed into the screw holes (8), the jig upper cover (4) and the jig bottom plate (5) can be locked.
5. The packaging auxiliary device for improving cavity surface damage during sintering of semiconductor chips according to claim 1, characterized in that: A plurality of drainage grooves (9) are provided on the side of the jig bottom plate (5), and the drainage grooves (9) are communicated with the inner side of the jig upper cover (4) and the ceramic back plate cleaning groove (7).
6. The packaging auxiliary device for improving cavity surface damage during sintering of semiconductor chips according to claim 1, characterized in that: The interior of the ceramic back plate cleaning groove (7) is provided with a chamfer, and the opening size of the ceramic back plate cleaning groove (7) is larger than the vertical size of the ceramic back plate (10).
7. The packaging auxiliary device for improving cavity surface damage during sintering of semiconductor chips according to claim 1, characterized in that: The jig upper cover (4) and the jig bottom plate (5) are both made of polytetrafluoroethylene plates.