Wafer PAD layer structure plated with AL layer

Abstract

The utility model provides a wafer PAD layer structure plated with an AL layer, which comprises a PAD layer and an AL layer, the PAD layer comprises a substrate layer and a metal layer, the metal layer comprises a titanium layer, the surface of the metal layer is plated with the AL layer, the AL layer comprises a first AL-containing layer and a third AL-containing layer, the material of the first AL-containing layer is selected from aluminum and / or copper, and the material of the third AL-containing layer is selected from aluminum and / or copper. The first AL-containing layer is connected with a base layer of a wafer PAD layer material, the third AL-containing layer is made of aluminum, the hardness of the first AL-containing layer is larger than or equal to 100 g / cm < 2 >, the hardness of the third AL-containing layer is smaller than or equal to 50 g / cm < 2 >, and the thickness ratio of the first AL-containing layer to the third AL-containing layer is 1: 1. The AL layer is coated according to the above layers, during subsequent packaging, no aluminum overflow can be realized in ball mounting, the eutectic property of IMC is not influenced, and the problems of reliability (demolding and high temperature) can be solved.

Description

Technical Field

[0001] The utility model relates to the technical field of wafer coating, in particular to a wafer PAD layer structure coated with an AL layer. Background Art

[0002] Semiconductor integrated circuits are electronic components that integrate many components into one chip to process and store various functions. Since semiconductor integrated circuits are produced by manufacturing multiple identical circuits on a thin substrate called a wafer, the wafer is the basis of semiconductors, just like making dough before adding ingredients when making pizza. Semiconductor integrated circuits are electronic components that integrate many components into one chip to process and store various functions.

[0003] Wafer refers to a disc made by slicing a single crystal column made of silicon (Si), gallium arsenide (GaAs), etc. into thin slices. Most wafers are made of silicon extracted from sand. At present, the performance of the M2 (PAD) layer material for wafer coating is unstable and the cost price is too high. In the actual application process, it is found that after the film is formed, the important performance indicators of the AL material such as stress, roughness, and reflection value will undergo uncontrollable changes. The AL layer in different forms has different effects on the quality of the package. Summary of the invention

[0004] In order to overcome the deficiencies in the prior art, the utility model provides a wafer PAD layer structure with an AL layer plated.

[0005] To achieve the above-mentioned object, the utility model provides a wafer PAD layer structure coated with an AL layer, which comprises a PAD layer and an AL layer, wherein the PAD layer comprises a substrate layer and a metal layer, wherein the metal layer comprises a titanium layer, and an AL layer is plated on the surface of the metal layer, wherein the AL layer comprises a first AL-containing layer and a third AL-containing layer, wherein the material of the first AL-containing layer is selected from aluminum and / or copper, the first AL-containing layer is connected to the base layer of the wafer PAD layer material, the material of the third AL-containing layer is selected from aluminum, and the hardness of the first AL-containing layer is greater than or equal to 100g / cm 2 The hardness of the third Al-containing layer is less than or equal to 50 g / cm 2 The thickness ratio of the first AL-containing layer to the third AL-containing layer is 1:1.

[0006] Preferably, a second Al-containing layer is provided between the first Al-containing layer and the third Al-containing layer, the material of the second Al-containing layer is selected from aluminum, and the hardness of the second Al-containing layer is 60-80 g / cm 2 .

[0007] Preferably, the thickness ratio of the first Al-containing layer, the second Al-containing layer and the third Al-containing layer is 2:1:2.

[0008] Preferably, the thickness of the Al layer structure is 1600nm-2800nm.

[0009] Preferably, the material of the first Al-containing layer is selected from one or more of aluminum-copper alloy, pure aluminum and pure copper.

[0010] The beneficial effects of the utility model are as follows:

[0011] The AL layer of the utility model is coated in accordance with the above-mentioned layered coating. When the subsequent packaging is performed, there can be no aluminum overflow during the ball planting, and there will be no problem with the eutectic property of IMC. The problems of reliability (demolding, high temperature) can be solved, thereby reducing the coating cost, solving the problem of poor IMC after the package ball planting is flipped, and improving the key performance of the AL layer after film formation. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a test diagram of the coating results of the AL layer coated in the utility model solution;

[0013] Figure 2 It is one of the wafer PAD layer structures coated with an AL layer in the utility model;

[0014] Figure 3 This is the second wafer PAD layer structure with an AL layer plated in the utility model. DETAILED DESCRIPTION

[0015] In order to better illustrate the purpose, technical solutions and advantages of the present invention, the present application will be further described below in conjunction with specific embodiments.

[0016] Example 1

[0017] The present embodiment provides a wafer PAD layer structure coated with an AL layer, which includes a PAD layer 1 and an AL layer 2. The PAD layer 1 includes a substrate layer 11 and a metal layer 12. The metal layer 12 is preferably a titanium layer. The surface of the metal layer 12 is coated with an AL layer 2. The AL layer 2 includes a first AL-containing layer 21 and a third AL-containing layer 23. The material of the first AL-containing layer is selected from aluminum and / or copper. The first AL-containing layer 21 is connected to the metal layer 12 of the wafer PAD layer material. The material of the third AL-containing layer 23 is selected from aluminum. The hardness of the first AL-containing layer 21 is greater than or equal to 100 g / cm 2 The hardness of the third Al-containing layer 23 is less than or equal to 50 g / cm 2 The thickness ratio of the first Al-containing layer 21 to the third Al-containing layer 23 is 1:1.

[0018] A second Al-containing layer 22 is disposed between the first Al-containing layer 21 and the third Al-containing layer 23. The material of the second Al-containing layer 22 is selected from aluminum. The hardness of the second Al-containing layer 22 is 60-80 g / cm 2The thickness ratio of the first Al-containing layer 21 , the second Al-containing layer 22 , and the third Al-containing layer 23 is 2:1:2.

[0019] The thickness of the Al layer structure is 1600nm-2800nm. The material of the first Al-containing layer is selected from aluminum-copper alloy, pure aluminum, and pure copper. Preferably, pure aluminum and pure copper are evaporated separately.

[0020] The first Al-containing layer (thickness 800nm), the hardness of aluminum ≥ 100g / cm 2 The second Al-containing layer (thickness 800nm) has a hardness of 60g / cm 2 -80g / cm 2 The third Al layer (400nm) makes the hardness of aluminum ≤50g / cm 2 For example, the performance of the wafer PAD layer after coating is as follows:

[0021]

[0022] The AL layer is coated according to the above layers. When the package is subsequently carried out, there will be no aluminum overflow during ball planting, and there will be no problem with the eutectic property of IMC. The problems of reliability (demolding, high temperature) can be solved, and the electrical performance cp and frequency will not be affected (the values ​​of each product are different).

[0023] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model rather than to limit the protection scope of the utility model. Although the utility model is described in detail with reference to the preferred embodiments, ordinary technicians in this field should understand that the technical solution of the utility model can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the utility model.

Claims

1. A wafer PAD layer structure with an AL layer, characterized in that: The invention comprises a PAD layer and an AL layer, wherein the PAD layer comprises a substrate layer and a metal layer, wherein the metal layer comprises a titanium layer, wherein an AL layer is plated on the surface of the metal layer, wherein the AL layer comprises a first AL-containing layer and a third AL-containing layer, wherein the material of the first AL-containing layer is selected from aluminum and / or copper, wherein the first AL-containing layer is connected to the base layer of the wafer PAD layer material, wherein the material of the third AL-containing layer is selected from aluminum, and wherein the hardness of the first AL-containing layer is greater than or equal to 100 g / cm 2 The hardness of the third Al-containing layer is less than or equal to 50 g / cm 2 The thickness ratio of the first AL-containing layer to the third AL-containing layer is 1:

1.

2. The wafer PAD layer structure coated with an Al layer according to claim 1, characterized in that: A second Al-containing layer is disposed between the first Al-containing layer and the third Al-containing layer. The material of the second Al-containing layer is selected from aluminum. The hardness of the second Al-containing layer is 60-80 g / cm 2 .

3. The wafer PAD layer structure coated with an Al layer according to claim 2, characterized in that: The thickness ratio of the first AL-containing layer, the second AL-containing layer and the third AL-containing layer is 2:1:

2.

4. The wafer PAD layer structure coated with an Al layer according to claim 1, characterized in that: The thickness of the Al layer structure is 1600nm-2800nm.

5. The wafer PAD layer structure coated with an Al layer according to claim 1, characterized in that: The material of the first Al-containing layer is selected from one or more of aluminum-copper alloy, pure aluminum and pure copper.

Images