JPH04131941U - semiconductor equipment - Google Patents

Abstract

(57) [Summary] [Objective] It is an object of the present invention to provide a semiconductor device that can always operate a semiconductor element normally and stably. [Structure] Ceramic base 1 with many metal wiring layers 3b
A semiconductor element A is placed on top of the semiconductor element A.
In the semiconductor device, each electrode of the ceramic substrate is connected to the metal wiring layer 3b via a TAB lead 5.
1 and the surface facing the semiconductor element A has a thickness of 3 to 3.
A 100 μm insulating protective film 6 was deposited. Insulating protective film
6 blocks alpha rays emitted from the ceramic substrate 1 and absorbs stress when the electrodes of the semiconductor element A come into contact with each other, thereby making it possible to always operate the semiconductor element A normally.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

The present invention is a semiconductor device in which a semiconductor element is housed in a package for housing the semiconductor element. This is related to improvements to the equipment.

0002

[Conventional technology]

Conventionally, information processing equipment such as computers has been equipped with semiconductor devices in packages for storing semiconductor devices. A semiconductor device is used that is hermetically housed in a cage.

0003 Semiconductor devices used in such information processing devices are usually made of alumina ceramics. It is made of an electrically insulating material such as a base, and the semiconductor element is housed approximately in the center of its upper surface. Tungsten (W) and molybdenum derived from the recess and the bottom surface from the periphery of the recess An insulating substrate with a metal wiring layer made of high melting point metal powder such as manganese (Mo) or manganese (Mn). Then, a silver plate is applied to the metal wiring layer to electrically connect the semiconductor element to an external electric circuit. A semiconductor element consisting of an external lead terminal attached via brazing material such as C and a lid body. A semiconductor device storage package is prepared, and then the insulating base of the semiconductor device storage package is prepared. Attach and fix the semiconductor element to the bottom of the recess using a soldering material such as gold-silicon eutectic solder. At the same time, each electrode of the semiconductor element is electrically connected to the metal wiring layer using a bonding wire. After that, the lid body is covered with a sealing material such as glass or resin on the top surface of the insulating base. A semiconductor element is hermetically sealed inside a container consisting of an insulating base and a lid. It is manufactured by

0004 However, in recent years, semiconductor devices have rapidly become denser and more highly integrated. The number of child electrodes is extremely large, and the spacing between adjacent electrodes is becoming extremely narrow. Bonding wires are used to connect each electrode of the semiconductor element and the metal wiring layer provided on the insulating substrate. When connected through a bonding wire, adjacent bonding wires Bending can easily cause a contact short circuit, resulting in the semiconductor device not being able to operate normally. This resulted in a drawback that made it impossible to do so.

[0005] Therefore, in order to eliminate the above-mentioned drawbacks, as shown in Fig. A semiconductor element 23 is placed on top of a ceramic base 22, and each of the semiconductor elements 23 is An electrode is connected to the metal wiring layer 21 via a TAB (Tape Automated Bonding) lead 24. Connected semiconductor devices have been proposed.

[0006] In such a semiconductor device, the TAB lead 24 is made of copper foil of a predetermined width on a polyimide film. The position of each copper foil is suppressed by a polyimide film. Therefore, there is no possibility of short circuits due to contact between adjacent copper foils, and each of the semiconductor elements 23 To accurately and reliably connect the electrode to the metal wiring layer 21 provided on the ceramic base 22. becomes possible.

[0007]

[Problem that the idea aims to solve]

However, in this semiconductor device, each electrode of the semiconductor element and the top surface of the ceramic substrate are The semiconductor element is electrically connected to the metal wiring layer provided on the The surface on which each electrode is formed will face the ceramic substrate, and the As a result, the following disadvantages are induced.

[0008] That is, (1) Ceramic substrates emit large amounts of α-rays from their surfaces, and these α-rays are When the electrode part of the semiconductor element facing the block substrate is irradiated, the characteristics of the semiconductor element change. changes, causing malfunctions in semiconductor devices. (2) Because the ceramic substrate has extremely high hardness, a half-layer is placed on the top of the ceramic substrate. When placing a conductor element, if the semiconductor element comes into contact with the ceramic substrate, each electric current of the semiconductor element The poles may be damaged, causing changes in the characteristics of the semiconductor device or loss of its function as a semiconductor device. I end up losing it. Such disadvantages are induced.

[0009]

[Means to solve the problem] This invention places a semiconductor element on top of a ceramic substrate that has multiple metal wiring layers. At the same time, each electrode of the semiconductor element is connected to the metal wiring layer via a TAB lead. In the semiconductor device formed by It is characterized by having an insulating protective film with a thickness of 3 to 100 μm applied to the surface. It is.

0010

【Example】

Next, the present invention will be explained in detail based on the accompanying drawings.

[0011] Figure 1 is a cross-sectional view showing one embodiment of the semiconductor device of the present invention. 2 is a lid, A is a semiconductor element, and the ceramic base 1 and lid 2 form a semiconductor element. A container for a semiconductor device storage package is constructed to accommodate the child A.

The ceramic substrate 1 constituting the package for housing semiconductor elements is made of an alumina sintered body, a mullite sintered body, an aluminum nitride sintered body, etc. For example, when it is made of an alumina sintered body, it is made of alumina ( A suitable organic solvent or solvent is added and mixed to raw material powders such as Al ₂ 0 ₃ ), silica (SiO ₂ ), calcia (C aO), and magnesia (MgO) to form a slurry, which is then processed using a well-known doctor blade. A ceramic green sheet (ceramic raw sheet) is formed by adopting the method, and then a suitable punching process is performed on the ceramic green sheet, multiple sheets are laminated, and the obtained ceramic green sheet is fired at a high temperature (approximately 1600℃). It will be done.

[0013] Furthermore, the ceramic base 1 has a plurality of pieces, one end of which extends to the top surface and the other end of which leads to the bottom surface. A metallized wiring layer 3a is buried, and the metallized wiring layer 3a is connected to the semiconductor element A. Connect each electrode to external lead pin 4, which is electrically connected to the external electric circuit described later. It has the effect of

[0014] The metallized wiring layer 3a is made of high melting material such as tungsten, molybdenum, manganese, etc. It consists of point metal powder, and is made by adding and mixing an appropriate organic solvent or solvent to the high melting point metal powder. The obtained metal paste is applied to ceramics using a well-known thick film method such as screen printing. By pre-adhering it to the ceramic green sheet that serves as the block substrate 1, It is buried inside the ramic base 1.

[0015] Further, the ceramic substrate 1 is connected to one end of the metallized wiring layer 3a on its lower surface. The external lead pin 4 is attached through a soldering material such as silver solder, and the corresponding External lead pin 4 is used to electrically connect each electrode of semiconductor element A to an external electric circuit. Do something.

[0016] The external lead pin 4 is made of, for example, Kovar metal (Fe-Ni-Co alloy) or 42 alloy. It is made of metals such as Fe-Ni alloy (Fe-Ni alloy), and is made of metals such as Kovar metal (Fe-Ni alloy). It is formed into a predetermined pin shape by using a known rolling method and punching method. It will be done.

[0017] In addition, the external lead pin 4 is coated with nickel (Ni), gold (Au), etc. on its exposed outer surface. A thickness of 1.0 to 20.0μm is achieved by plating a metal with excellent corrosion resistance and good conductivity. By placing a layer on the external lead pin 4, the electrical connection between the external lead pin 4 and the external electric circuit will be ensured. Ru. Therefore, the external lead pin 4 has nickel (Ni), gold (Au, etc.) on its exposed outer surface. It is preferable to form a layer with a thickness of 1.0 to 20.0 μm.

[0018] The ceramic substrate 1 also has a metal layer formed on its upper surface by a thin film forming technique. A wiring layer 3b is deposited with one end thereof in contact with the metallized wiring layer 3a. The metal wiring layer 3b has a TAB connected to an electrode of a semiconductor element A, which will be described later. Lead 5 is joined.

[0019] The metal wiring layer 3b includes, for example, an adhesive layer made of titanium (Ti) and a titanium tungsten steel layer. It has a three-layer structure: a barrier layer made of copper alloy (Ti-W) and a main conductor layer made of copper (Cu). Therefore, thin film formation techniques such as vapor deposition and sputtering are applied to the top surface of the ceramic substrate 1. Titanium as an adhesive layer, titanium as a barrier layer, tungsten alloy and Copper as a conductive layer is deposited to a predetermined thickness, and the adhesive layer, barrier layer and conductive layer are Each layer of the body is etched into a predetermined pattern using photolithography technology. It is formed into a predetermined shape.

[0020] Note that the adhesive layer constituting the metal wiring layer 3b connects the ceramic substrate 1 and the metal wiring layer 3b. If the thickness is less than 0.01 μm, the metal wiring layer 3b It becomes difficult to firmly bond the Ceramic substrate 1 and the adhesive layer tends to decrease. Therefore, the thickness of the adhesive layer is 0. It is preferably in the range of 0.01 to 1.0 μm, preferably in the range of 0.03 to 0.5 μm.

[0021] Furthermore, the barrier layer deposited on the upper surface of the adhesive layer has the function of preventing mutual diffusion between the adhesive layer and the main conductor layer, as well as firmly bonding the adhesive layer and the main conductor layer, and has the function of If the thickness is less than 0.1 μm, mutual diffusion between the adhesive layer and the main conductor layer cannot be effectively prevented, and if it exceeds 5.0 μm, internal stress may occur when the barrier layer is deposited using thin film formation technology. The bonding strength between the adhesive layer and the barrier layer tends to decrease. Therefore, the thickness of the barrier layer is in the range of 0.1 to 5.0 μm, preferably 0.1 to 5.0 μm.
It is preferable to keep it in the range of 5 to 3.0 μm.

[0022] Furthermore, the composition of the titanium tungsten alloy constituting the barrier layer is based on the titanium content. When it is 0.2% by weight, the bonding strength between the adhesive layer and the barrier layer decreases, and when it is 30.0% by weight, When the hardness of the barrier layer is exceeded, the internal stress of the main conductor layer formed on it increases. The bonding strength between the barrier layer and the main conductor layer tends to decrease as it becomes difficult to relax.

[0023] Therefore, the titanium content in the barrier layer is 0.2 to 30.0% by weight, especially 3.0 to 30.0% by weight. It is preferable to set it at 20.0% by weight.

[0024] Further, the main conductor layer deposited on the upper surface of the barrier layer mainly serves as a path for conducting electricity. For example, copper (Cu), which has extremely low conduction resistance, is used, and its thickness is 0.1 If it is less than μm, the conduction resistance of the metal wiring layer 3b becomes high and each electrode of the semiconductor element A is This tends to make it impossible to make a good electrical connection to the metallized wiring layer 3a. Therefore, it is preferable to set it to 0.1 μm or more, and considering the cost, it is 0.1 to 15.0 μm, preferably in the range of 0.5 to 10.0 μm.

[0025] Semiconductor elements A are also arranged at regular intervals on the upper surface of the ceramic substrate 1. Each electrode of the semiconductor element A is made of metal deposited on the top surface of the ceramic substrate 1. It is connected to the wiring layer 3b via the TAB lead 5, thereby connecting each voltage of the semiconductor element A. The poles are TAB leads 5, external leads via metal wiring layer 3b and metallized wiring layer 3a. It will be electrically connected to pin 4.

[0026] The TAB leads 5 connecting each electrode of the semiconductor element A to the metal wiring layer 3b are, for example, For example, a polyimide film is coated with a large number of copper foils of a predetermined width, and each copper foil is coated with a polyimide film. The distance between adjacent copper foils is extremely narrow because their position is suppressed by the foil film. Even if the material is It becomes possible to accurately and reliably electrically connect each electrode of A to the metal wiring layer 3b. .

[0027] In addition, the TAB lead 5 is made of copper foil and epoxy resin etc. on the entire surface of the polyimide film. After that, the copper foil is etched into a predetermined pattern. The TAB lead 5, each electrode of the semiconductor element A, and the metal wiring layer 3b were manufactured by The joining is performed using a brazing material such as solder.

[0028] Further, on the upper surface of the ceramic substrate 1, the surface facing the semiconductor element A has a thickness of 3 An insulating protective film 6 with a thickness of 100 μm to 100 μm is deposited, and the insulating protective film 6 is made of Teflon. or polyimide, etc., and can be applied using thick film techniques such as screen printing, photo etching, etc. By adopting the etching process method and heat treatment method, the top surface of the ceramic substrate 1 is be coated.

[0029] The insulating protective film 6 blocks the α rays emitted from the ceramic substrate 1 and prevents the α rays from being emitted. It has the effect of effectively preventing irradiation from being applied to the electrode part of semiconductor element A. Therefore, semiconductor device A has constant characteristics and operates normally and stably over a long period of time. It becomes possible to

[0030] Further, the insulating protective film 6 made of Teflon, polyimide, etc. is formed on the ceramic substrate 1. When placing semiconductor element A on top of ceramic substrate 1, it is softer than ceramic substrate 1. Each electrode of the semiconductor element A is attached to an insulating protective film 6 deposited on the top surface of the ceramic substrate 1. Even if they make contact, the stress will be absorbed by the insulating protective film 6 and each electrode of the semiconductor element A will be damaged. This rarely happens, and this also allows semiconductor element A to always operate normally. Becomes Noh.

[0031] Note that if the thickness of the insulating protective film 6 is less than 3 μm, the insulating protective film 6 is When it becomes impossible to effectively block alpha rays emitted from the lamic substrate 1, The semiconductor element A is unable to absorb the stress when it comes into contact with the semiconductor element A. If the thickness exceeds 100 μm, the insulating protective film may change. Due to the internal stress generated when depositing the insulating protective film 6 on the ceramic substrate, 1 The top surface peels off and the insulating protective film 6 loses its function. The thickness of the membrane 6 is specified to be in the range 3 to 100 μm.

[0032] Further, the insulating protective film 6 is made of a soft and electrically insulating material that can block alpha rays. It may be made of any material, but Teflon and polyimide are ceramic-based. It is softer than body 1, completely blocks alpha rays, and adheres firmly to ceramic base 1. Therefore, Teflon or polyimide should be used as the insulating protective film6. is preferred.

[0033] Thus, there is a ceramic substrate on the top surface of which the semiconductor element A is connected via the TAB lead. Body 1 further has a sealing material such as glass, resin, brazing material, etc. on the outer periphery of its upper surface and the lower end of lid body 2. The semiconductor element A is bonded to the inside of the container consisting of the ceramic substrate 1 and the lid 2. A semiconductor device is completed by airtightly encapsulating the semiconductor device.

[0034]

[Effect of the idea]

According to the present invention, a semiconductor element is placed on top of a ceramic substrate having a large number of metal wiring layers. and each electrode of the semiconductor element is connected to the metal wiring layer via a TAB lead. In the semiconductor device, the semiconductor element is connected to the top surface of the ceramic substrate. Since an insulating protective film with a thickness of 3 to 100 μm is deposited on the facing surface, The alpha rays emitted from the semiconductor substrate are directed to the electrodes of the semiconductor element by an insulating protective film. This effectively prevents radiation from irradiating the semiconductor device, resulting in changes in the characteristics of the semiconductor device. To keep semiconductor devices operating normally and stably for a long period of time without any changes. It becomes possible to

[0035] In addition, since the insulating protective film is softer than the ceramic substrate, it When placing a semiconductor element on the top of the substrate, insulation applied to the top surface of the ceramic substrate Even if each electrode of the semiconductor element comes into contact with the protective film, the stress is absorbed by the insulating protective film and reduced by half. There is almost no damage to the electrodes of the conductive element, and this also ensures that the semiconductor element is always It becomes possible to operate normally.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an embodiment of a semiconductor device of the present invention.

FIG. 2 is a cross-sectional view showing a conventional semiconductor device.

[Explanation of symbols]

1...Ceramic base 2... Lid body 3a...metalized wiring layer 3b...metal wiring layer 4...External lead pin 5...TAB read 6...Insulating protective film

Claims (3)

[Scope of utility model registration request] 1. A semiconductor device comprising: a semiconductor element disposed on top of a ceramic substrate having a large number of metal wiring layers; and each electrode of the semiconductor element connected to the metal wiring layer via a TAB lead; 1. A semiconductor device characterized in that an insulating protective film with a thickness of 3 to 100 μm is deposited on the upper surface of a base body, which faces a semiconductor element. 2. The semiconductor device according to claim 1, wherein the insulating protective film is made of an electrically insulating material capable of blocking alpha rays irradiated from the ceramic substrate. 3. The semiconductor device according to claim 1, wherein the insulating protective film is made of polyimide or Teflon.