CN-116240600-B - Ceramic electroplating process

CN116240600BCN 116240600 BCN116240600 BCN 116240600BCN-116240600-B

Abstract

The invention relates to the technical field of electroplating, in particular to a ceramic electroplating process, which comprises the steps of carrying out first-step corrosion on conductive paste solidified at one end of a through hole of a ceramic substrate to be plated to form a first electroplating surface, carrying out second-step corrosion on an unplated end surface of the conductive paste after the first-step electroplating surface is electroplated to form a second electroplating surface, carrying out electroplating again on the second electroplating surface to complete electroplating on the through hole of the ceramic substrate, determining corrosion time according to average unit corrosion height in the corrosion process, determining electroplating time according to average actual corrosion height in the electroplating process, and reducing the height of the through hole when the size ratio of the radius to the height of the through hole is small in each electroplating by adopting a mode of carrying out first corrosion and then electroplating on two ends of the conductive paste in the through hole of the ceramic substrate to be plated, thereby ensuring the electroplating efficiency of a plating layer in the deposition process from bottom to top in the through hole.

Inventors

CHEN SHAOSHU
LU JUAN
TANG LIN

Assignees

北京华江文化集团有限公司

Dates

Publication Date: 20260512
Application Date: 20221116

Claims (10)

1. A ceramic electroplating process comprising: step S1, filling conductive paste into each through hole of a ceramic substrate to be plated and curing, and determining one-time expected corrosion height of the conductive paste in the through hole according to the height of the through hole; Step S2, performing first-step corrosion on the conductive paste solidified at one end of the through hole by using a corrosive agent, wherein the first-step corrosion time is determined according to the first-step average unit corrosion height of the through hole, and the first-step average actual corrosion height is determined according to the first-step actual corrosion height of each through hole; step S3, cleaning the through hole after the first step corrosion under the primary electroplating starting condition, and marking the end face of the conductive paste in the through hole after the first step corrosion as a primary electroplating surface; s4, primary electroplating is carried out on the primary electroplating surface, and the electroplating time of the primary electroplating surface is determined according to the average actual corrosion height in the first step; Step S5, cleaning and drying the ceramic substrate in sequence under the condition of one-time electroplating completion, sputtering a seed layer on a first reference surface, electroplating the first reference surface, and then performing a second-step corrosion on the end surface of the conductive paste, which is not electroplated, by using a corrosive agent, wherein the second-step corrosion height of the conductive material in the through hole is determined according to the first-step corrosion height, the actual corrosion rate of the first-step corrosion is determined according to the corrosion time after the first-step corrosion is regulated so as to determine the corrosion time of the second-step corrosion, and the second-step average actual corrosion height is determined according to the second-step actual corrosion height of each through hole; Step S6, cleaning the through hole after the second step corrosion under the secondary electroplating starting condition, and marking the end surface, which is in contact with the corrosive agent, in the through hole after the second step corrosion as a secondary electroplating surface; s7, performing secondary electroplating on the secondary electroplating surface, and determining the electroplating time of the secondary electroplating surface according to the average actual corrosion height in the second step; step S8, cleaning and drying the ceramic substrate in sequence under the secondary electroplating completion condition, sputtering a seed layer on a second reference surface and electroplating the second reference surface to complete the electroplating filling of the through holes and the electroplating of the ceramic substrate; The first electroplating starting condition is that the average actual corrosion height of the first step is more than or equal to the first expected corrosion height, the first electroplating finishing condition is that the average height of the through hole from the first reference surface after the first electroplating is more than or equal to 0, the second electroplating starting condition is that the average actual corrosion height of the second step is more than or equal to the second expected corrosion height, and the second electroplating finishing condition is that the average height of the through hole from the second reference surface after the second electroplating is more than or equal to 0; The first reference surface is the surface of the ceramic substrate to be plated, which is connected with the hole end of the through hole to be subjected to the first-step corrosion, and the second reference surface is the surface of the ceramic substrate to be plated, which is connected with the hole end of the through hole to be subjected to the second-step corrosion.
2. The ceramic electroplating process according to claim 1, further comprising step S0, wherein the central control unit determines whether to use the ceramic electroplating process to electroplate the ceramic substrate to be plated according to a ratio DeltaRH of a radius R and a height H of the through hole of the ceramic substrate to be plated, the central control unit is provided with a preset ratio DeltaRHO, deltaRH=R/H is set, If DeltaRH is less than or equal to DeltaRHO, the central control unit judges that the ceramic substrate to be plated is electroplated by using the ceramic electroplating process; And if DeltaRH > DeltaRHO, the central control unit judges that the ceramic substrate to be plated is not plated by using the ceramic plating process.
3. The ceramic plating process according to claim 2, wherein in the step S1, the central control unit determines a primary desired etching height HQ1 of the conductive paste according to the height H of the through hole, the central control unit being provided with a first through hole height H1, a second through hole height H2, a first height coefficient H1, a second height coefficient H2, and a third height coefficient H3, wherein H1< H2,0< H1< H2< H3<0.5, When H is less than or equal to H1, the central control unit adopts a first height coefficient H1 to determine a primary expected corrosion height HQ1 and sets HQ1=H21; When H1 is less than or equal to H2, the central control unit adopts a second height coefficient H2 to determine a primary expected corrosion height HQ1 and sets HQ1=H2Xh 2; when H > H2, the central control unit determines a once desired corrosion height HQ1 using a third height coefficient H3 and sets hq1=hxh3.
4. The ceramic plating process according to claim 3, wherein in the step S2, the central control unit calculates an average unit etching height according to the first step The ratio delta B of the standard unit corrosion height G0 determines the regulation mode of the corrosion time of the first step corrosion, the central control unit is provided with a first preset ratio delta B1, a second preset ratio delta B2, a first corrosion time coefficient t1 and a second corrosion time coefficient t2, wherein 0.8< delta B1<1< delta B2<1.2,0< t2<1< t1<1.5, and the regulation mode is set G i is the first step of the etch height per unit time t for the ith via, n is the total number of vias, i=1, 2,3, n, When Δb is less than or equal to Δb1, the central control unit determines to adjust the corrosion time of the first step of corrosion by using a first corrosion time coefficient T1, the central control unit marks the adjusted corrosion time of the first step of corrosion as Ta, and ta=t0×t1 is set, wherein T0 is the initial corrosion time of the first step of corrosion; When Δb1< Δb is less than or equal to Δb2, the central control unit determines that the corrosion time of the first step of corrosion does not need to be adjusted, and the central control unit sets ta=t0; when Δb > Δb2, the central control unit determines that the etching time of the first etching step is adjusted by using the second etching time coefficient T2, and sets ta=t0×t2.
5. The ceramic plating process according to claim 4, wherein in the step S2, the central control unit averages the actual etching height according to the first step The comparison result with the primary expected corrosion height HQ1 judges whether the through hole meets the primary electroplating starting condition, If it is The central control unit judges that the through hole meets the primary electroplating starting condition, and executes step S3; If it is The central control unit judges that the through hole does not meet the primary electroplating starting condition, and continues to execute the step S2; Wherein the first step averages the actual corrosion height Is the average value of the actual etching height of the first step of the conductive paste in each through hole after the first step of etching.
6. The ceramic plating process according to claim 5, wherein in the step S4, the central control unit averages an actual etching height according to the first step Determining the plating time Da for the primary plating surface, wherein the central control unit is provided with a first corrosion height G1, a second corrosion height G2, a first plating time coefficient d1, a second plating time coefficient d2 and a third plating time coefficient d3, wherein G1< G2, d1< d2< d3, When (when) When the central control unit judges that the first electroplating time coefficient D1 is adopted to calculate the electroplating time Da, and Da=D0×d1 is set, wherein D0 is the initial electroplating time of the primary electroplating surface; When (when) When the central control unit judges that the plating time Da is calculated by adopting a second plating time coefficient D2, da=D0×d2 is set, When (when) When the central control unit determines to calculate the plating time Da using the third plating time coefficient D3, the central control unit sets da=d0×d3.
7. The ceramic plating process according to claim 6, wherein in the step S4, the central control unit determines an average height from the first reference surface after the through holes are plated once Determining whether primary electroplating is completed, wherein the height of the through hole lower than the first reference surface after primary electroplating is marked as a negative value, the height of the through hole higher than the first reference surface after primary electroplating is marked as a positive value, and setting Mi is the height from the ith through hole to the first datum plane after primary electroplating, If it is The central control unit judges that primary electroplating is not finished, and continues to execute the step S4; If it is And the central control unit judges that the primary electroplating is finished and executes step S5.
8. The ceramic plating process according to claim 7, wherein in the step S4, the central control unit determines an average height from the first reference surface after the through holes are plated once The regulation mode of the electroplating time Da is determined by the ratio delta R between the central control unit and the standard distance height M0, wherein the central control unit is provided with a third preset ratio delta R1, a fourth preset ratio delta R2, a fourth electroplating time coefficient k1, a fifth electroplating time coefficient k2 and a sixth electroplating time coefficient k3, wherein delta R1< delta R2,1< k2< k3<1.5, and the central control unit is set M0>0, When Δr is less than or equal to Δr1, the central control unit determines that the plating time Da is adjusted by using a fourth plating time coefficient k1, marks the adjusted plating time of the primary plating surface as Dat, and sets dat=da×k1; When Δr1< Δr is less than or equal to Δr2, the central control unit determines that the plating time Da is adjusted by using a fifth plating time coefficient k2, and dat=da×k2 is set; When Δr > Δr2, the central control unit determines to adjust the plating time Da using a sixth plating time coefficient k3, and sets dat=da×k3.
9. The ceramic plating process according to claim 8, wherein in the step S5, the central control unit determines the etching time Tb of the second-step etching based on the actual etching rate v of the first-step etching, sets tb=μ×hq2/v, Wherein HQ2 is the secondary expected corrosion height, mu is the second step corrosion regulation coefficient, HQ2 is more than or equal to H-HQ1, and 1< mu <1.2.
10. The ceramic plating process according to claim 9, wherein in the step S5, the central control unit averages the actual etching height according to the second step The comparison result with the secondary expected corrosion height HQ2 judges whether the through hole meets the secondary electroplating starting condition, If it is The central control unit judges that the through hole meets the secondary electroplating starting condition and executes step S6; If it is The central control unit judges that the through hole does not meet the secondary electroplating starting condition, and continues to execute the step S5; Wherein the second step averages the actual corrosion height Is the average value of the actual etching height of the second step of the conductive material in each through hole after the second step of etching.

Description

Ceramic electroplating process Technical Field The invention relates to the technical field of electroplating, in particular to a ceramic electroplating process. Background With the high-speed development of products with high working current, high temperature and high frequency such as semiconductor power modules, high-power integrated circuits, 5G equipment and the like, higher requirements are put forward on carriers of chips. The ceramic material has stable chemical property, good electrical insulation, excellent high-frequency characteristic, high heat conductivity, low dielectric constant and very similar linear expansion coefficient to electronic components, and is widely applied to the field of electronic substrates, but because ceramics have no conductivity, the bonding strength of a metal circuit layer and a ceramic substrate and electroplating filling holes are key of the reliability of the ceramic substrate and key technology for preparing the ceramic substrate, the electroplating filling holes are key technology of the ceramic substrate, and the realization of void-free filling in through holes is a core requirement for realizing filling holes. Chinese patent publication No. CN114921821A discloses a through hole filling electroplating device and a TGV/TCV hole metallization method, wherein a conductive backboard is attached to the back of a plating piece to realize bottom-up plating of a non-conductive through hole bottom serving as a cathode, and a mechanical stirring mode is adopted to perform hole filling electroplating on the plating piece. In this technical scheme, electrically conductive backplate comprises conducting layer and peel ply, and the peel ply can be guaranteed to electroplate the separation of back conducting backplate and plating piece of filling the hole completion to agitating unit forms strong liquid exchange through carrying out controllable rotation of speed in the middle of the plating bath, accelerates the inside electroplating speed in hole, thereby reduces the inside problem that has hollow because of the inside hole that leads to of the untimely plating bath exchange in hole, but under the small circumstances of through-hole radius and high size ratio, the plating is at the inside in-process of depositing from bottom to top of through-hole, carries out the exchange efficiency of plating bath exchange through mechanical stirring not high, has the problem of electroplating inefficiency. Disclosure of Invention Therefore, the invention provides a ceramic electroplating process which is used for solving the problem of low electroplating efficiency in the process of depositing a coating inside a through hole from bottom to top when the size ratio of the radius to the height of the through hole is small in the prior art. In order to achieve the above object, the present invention provides a ceramic electroplating process comprising: step S1, filling conductive paste into each through hole of a ceramic substrate to be plated and curing, and determining one-time expected corrosion height of the conductive paste in the through hole according to the height of the through hole; Step S2, performing first-step corrosion on the conductive paste solidified at one end of the through hole by using a corrosive agent, wherein the first-step corrosion time is determined according to the first-step average unit corrosion height of the through hole, and the first-step average actual corrosion height is determined according to the first-step actual corrosion height of each through hole; step S3, cleaning the through hole after the first step corrosion under the primary electroplating starting condition, and marking the end face of the conductive paste in the through hole after the first step corrosion as a primary electroplating surface; s4, primary electroplating is carried out on the primary electroplating surface, and the electroplating time of the primary electroplating surface is determined according to the average actual corrosion height in the first step; Step S5, cleaning and drying the ceramic substrate in sequence under the condition of one-time electroplating completion, sputtering a seed layer on a first reference surface, electroplating the first reference surface, and then performing a second-step corrosion on the end surface of the conductive paste, which is not electroplated, by using a corrosive agent, wherein the second-step corrosion height of the conductive material in the through hole is determined according to the first-step corrosion height, the actual corrosion rate of the first-step corrosion is determined according to the corrosion time after the first-step corrosion is regulated so as to determine the corrosion time of the second-step corrosion, and the second-step average actual corrosion height is determined according to the second-step actual corrosion height of each through hole; Step S6, cleaning the through hole after the second step corrosion under the se