KR20150014685A - Plating solution containing Au-Pd alloy for manufacturing PPF plating-layer of semiconductor leadframe - Google Patents

Abstract

According to the present invention, disclosed is an ultra-thin gold-palladium alloy plating solution for forming the PPF plating layer of a semiconductor lead frame. The ultra-thin gold-palladium alloy plating solution for forming the PPF plating layer of a semiconductor lead frame is a plating solution which forms a plating layer on the surface of a lead frame during a semiconductor manufacturing process. The plating solution includes at least one selected from a group comprising potassium gold (I) cyanide, potassium gold (III) cyanide, gold (III) chloride hydrate, and sodium gold sulfite; and at least one selected from a group comprising dichloro tetraammonium palladium, palladium chloride anhydrous, palladium (II) acetate, palladium (II) nitrate, and palladium (II) cyanide. Accordingly, the manufacturing efficiency of a semiconductor process can be increased by securing adhesion, corrosion resistance, and wirebondability properties.

Description

[0001] The present invention relates to an ultra-thin gold-palladium alloy plating solution for forming a PPF plating layer of a semiconductor lead frame (plating solution containing Au-Pd alloy for manufacturing PPF plating-layer of a semiconductor leadframe)

The present invention relates to an ultra-thin gold-palladium alloy plating solution for forming a PPF plating layer of a semiconductor lead frame, and more particularly to a plating solution for a gold-palladium alloy plating solution for improving the manufacturing efficiency of a semiconductor process by securing adhesion and corrosion resistance as well as wirebondability Ultra-thin gold-palladium alloy plating liquid for forming a PPF plating layer of a semiconductor lead frame.

2. Description of the Related Art In general, a semiconductor process is composed of two processes: a leadframe manufacturing process for manufacturing a frame of a leadframe and a chip on the top of the manufactured leadframe. IC package process.

In the above two processes, a plating layer which is laminated using essentially the respective plating liquid is used.

In the leadframe process, when a plating layer is formed of copper or a copper alloy or a nickel or nickel alloy on the surface thereof and a chip is laid on the surface of the nickel / nickel alloy layer by soldering to form a plating layer, chip can be manufactured.

In order to solve the problem of reducing the manufacturing efficiency by increasing the number of air holes through the plating process in both the lead frame process and the package process, the two processes are greatly reduced to one process by using the free plate frame (PPF, Pre -Plated Frame.

This free plate frame realizes the simplification of the work process and the reduction of the semiconductor cost due to this, and since the soldering plating is not performed, the lead (Pb) can be removed from the process, and the advantage of being environmentally friendly can be obtained.

However, such a free plate frame has poor adhesion and corrosion resistance, resulting in frequent defects during or during the process.

Accordingly, an object of the present invention is to provide an ultra-thin gold-palladium alloy plating solution for forming a PPF plating layer of a semiconductor lead frame that secures adhesion, corrosion resistance, and wirebondability, .

The present invention is a plating solution for forming an ultra-thin gold-palladium alloy plating layer used in a PPF process of a semiconductor lead frame, wherein the plating solution contains potassium metal (I) as a source of the gold component of the plating layer, ) Potassium gold (I) cyanide, Potassium gold (III) cyanide, Gold (III) chloride hydrate and Sodium gold sulfite And at least one selected from the group consisting of palladium tetraammonium palladium, palladium chloride anhydrous, palladium (II) acetate, palladium nitrate At least one selected from the group consisting of palladium (II) nitrate and palladium (II) cyanide For the PPF plated layer of the semiconductor lead frame as ranging form ultra thin film of gold-palladium alloy and provides a plating solution.

According to an embodiment of the present invention, the plating solution may contain sodium hydrogen phosphate, potassium cyanide, potassium tartrate, sodium sulfate, ) Or sodium citrate may be further included.

According to another embodiment of the present invention, the plating solution may contain a conductive agent such as Potassium hydrogen, Sodium hydrogen, Potassium carbonate, Lactic acid, Malic acid, Or sodium gluconate may be further included.

According to another embodiment of the present invention, the plating solution may further include a chelating agent such as sodium-EDTA, nitrilo triacetic acid, or polyimide.

According to another embodiment of the present invention, the plating solution may further contain stabilizer Glycine, glycerin, phosphoric acid, or boric acid.

According to another embodiment of the present invention, the plating solution may contain at least one selected from the group consisting of polyethylene glycol tert-octyl phenyl ether, alkyl di- yryl ether disulfonate sodium salt, ethylenediamine diamine, or polyethylene glycol sulfuric acid.

According to the ultra-thin gold-palladium alloy plating solution for forming the PPF plating layer of the semiconductor lead frame according to the present invention, the adhesion and corrosion resistance as well as wirebondability are ensured, thereby improving the manufacturing efficiency of the semiconductor process.

Hereinafter, the present invention will be described in more detail.

In the plating solution for forming the ultra thin gold-palladium alloy plating layer used in the PPF process of the semiconductor lead frame according to the present invention, the plating solution is a potassium metal (I) cyanide at least one selected from the group consisting of cyanide, cyanide, potassium cyanide, gold (III) chloride hydrate and sodium gold sulfite, Dichloro tetraammonium palladium, Palladium chloride anhydrous, Palladium (II) acetate, Palladium (II) nitrate and the like were used as the source of the palladium component of the plated layer. And at least one selected from the group consisting of palladium (II) cyanide.

The above potassium (I) cyanide, potassium (III) cyanide, gold (III) chloride hydrate and sodium gold sulfite Sodium gold sulfite) is used as a source for providing gold particles to the plating solution, and the concentration may be in the range of 2 to 15 g / l of aqueous solution.

In addition, the above-mentioned dichlorotetraammonium palladium, palladium chloride anhydrous, palladium (II) acetate, palladium (II) nitrate and palladium cyanide Palladium (II) cyanide), which may be in the range of 0.2 to 10 g / l of aqueous solution.

The plating solution may further include a conductive salt in addition to gold and palladium. Examples of the plating solution include sodium hydrogen phosphate, potassium cyanide, potassium tartrate, sodium sulfate, Or sodium citrate. ≪ / RTI >

In order to double the characteristics of the conductive salt, the plating solution further includes a conductivity enhancer, which may be selected from the group consisting of Potassium hydrogen, Sodium hydrogen, Potassium carbonate, Lactic acid, Malic acid or sodium gluconate may be optionally used.

In addition, a chelating agent may be used in the plating solution to adsorb metal ions to contribute to the formation of a plating layer. For example, sodium-EDTA, nitrilo triacetic acid, or polyimide may be used. .

On the other hand, a stabilizer may be used for the storage stability of the plating solution or for forming a uniform plating layer after the plating process. Examples of the stabilizer include Glycine, Glycerin, Phosphoric acid or Boric acid .

The plating solution may contain at least one selected from the group consisting of polyethylene glycol tert-octyl phenyl ether, alkyl diaryl ether disulfonate sodium salt, ethylenediamine or polyethylene glycol sulfurous acid (Polyethylene glycol sulfuric acid).

Example 1

Sodium hydrogen 30 g / ℓ, Sodium gluconate 20 g / ℓ, Nitrilo triacetic acid 2 g / ℓ, and Polyethylene glycol sulfuric acid 0.5 g / ℓ, Potassium gold (I) cyanide 12 g / ℓ, Dichlorotetraammonium palladium 3 g / m 2 and a plating time of 5 seconds to obtain a plating solution having a weight ratio of Au to Pd of 98: 2, a plating thickness of 0.0055 탆 A plated layer was formed as a top layer of a semiconductor lead frame made of a copper alloy.

Example 2

Potassium cyanide 120 g / l, Potassium hydrogen 50 g / l, Potassium carbonate 30 g / l, Glycine 20 g / l, Sodium-EDAT 10 g / l, Potassium cyanide 11 g / / l and polyethylene glycol tertoctyl phenylether at a current density of 1 A / m < 2 > and a plating time of 5 seconds to prepare a plating solution having a pH of 13, A plating layer having a top layer of Au: Pd ratio of 92: 8 and a plating thickness of 0.0055 mu m was formed.

Example 3

1 g / ℓ of Potassium gold (III) cyanide, 8 g / ℓ of Dichloro tetraammonium palladium, 100 g / ℓ of Potassium tartrate, 50 g / ℓ of Lactic acid, 30 g / ℓ of Boric acid, 5 g / ℓ of Polyimide, And a plating solution having a pH of 5.8 was prepared. The plating solution was treated at a current density of 1 A / m < 2 > and a plating time of 5 seconds at a working temperature of 55 DEG C to form a top layer of a semiconductor lead frame made of a copper alloy, A weight ratio = 90: 10, and a plating thickness of 0.0055 mu m.

Example 4

Sodium citrate 70 g / ℓ, Malic acid 45 g / ℓ, Phosphoric acid 5 g / ℓ, Nitrilo triacetic acid 5 g / ℓ, Alkyl diurylether disulfonate sodium (0.2 g / l) to prepare a plating solution having a pH of 3.6. The plating solution was treated at a current density of 1 A / m < 2 > and a plating time of 5 seconds to maintain a working temperature of 55 [deg.] C to form a top layer of a semiconductor lead frame , A weight ratio of Au to Pd = 97: 3, and a plating thickness of 0.0055 mu m was formed.

Example 5

Sodium sulfite 5 g / ℓ, Palladium II acetate 1 g / ℓ, Sodium sulfate 60 g / ℓ, Sodium gluconate 45 g / ℓ, Glycine 15 g / ℓ, Sodium EDTA 5 g / ℓ and Ethylene diamine 0.7 g / M 2 and a plating time of 5 seconds to obtain a top layer of a semiconductor lead frame made of a copper alloy and having a weight ratio of Au to Pd = 94: 6, and a plating layer having a thickness of 0.0055 mu m was formed.

Example 6

Sodium citrate, 50 g / l, Lactic acid, 15 g / l, Polyimide, 5 g / l, Polyethylene glycol sulfuric acid, 1 g / And a plating solution having a pH of 6.5 was prepared. The plating solution was treated at a current density of 1 A / m < 2 > and a plating time of 5 seconds at a working temperature of 55 DEG C to form a top layer of a semiconductor lead frame made of a copper alloy, A weight ratio of 99: 1, and a plating thickness of 0.0055 mu m.

EXPERIMENTAL EXAMPLE 1 Evaluation of Adhesion

The plating layer according to Examples 1 to 6 was subjected to heat treatment at 395 DEG C for 2 minutes to confirm blistering, peeling, and lifting with a microscope and the naked eye. After peeling off the plating layer with a cutter knife, Respectively.

In addition, Scotch tape (3M Scotch tape - # 540, # 610) was tightly adhered to the plated layer and strongly adhered to the plated layer. However, peeling or lifting did not occur.

Experimental Example 2 Evaluation of corrosion resistance

The plating layer according to Examples 1 to 6 was subjected to a heat treatment at 395 DEG C for 2 minutes and then left in a brine spray tester in which a 5% aqueous solution of NaCl was sprayed, at 40 DEG C for 24 hours and then taken out and examined for microscopic and visual corrosion. No rise, peeling, or lifting occurred.

Experimental Example 3 Evaluation of Wire Bondability

The plating layer according to Examples 1 to 6 was subjected to a heat treatment at 395 DEG C for 2 minutes and a bonding full test was performed at a temperature of 200 to 220 DEG C using a gold wire, By measuring the force, the acceptance criterion of this test is a full value of 5 g or more.

The results of adhesion evaluation, corrosion resistance evaluation and wire bondability evaluation are shown in Table 1 below.

Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Adhesiveness O O O O O O Corrosion resistance O O O O O O Wire
bondability O O O O O O

(O indicates excellent, X indicates poor)

Referring to Table 1, when the characteristics of the plating solution according to the present invention is used as a plating layer of a semiconductor lead frame, it can be confirmed that the adhesion, corrosion resistance, and wire bondability are excellent.

Claims (6)

In a plating solution for forming an ultra thin gold-palladium alloy plating layer used in a PPF process of a semiconductor lead frame,
Potassium gold (I) cyanide, Potassium gold (III) cyanide, Gold chloride (III) cyanide, and Gold chloride (III) cyanide were used as the source of the gold component of the plating layer. chloride hydrate and sodium gold sulfite, and at least one selected from the group consisting of sodium chloride,
Dichloro tetraammonium palladium, Palladium chloride anhydrous, Palladium (II) acetate, Palladium (II) nitrate and the like were used as the source of the palladium component of the plated layer. Palladium (III) cyanide, and palladium (II) cyanide. 2. The ultra-thin gold-palladium alloy plating solution for forming a PPF plating layer of a semiconductor lead frame according to claim 1,
The method according to claim 1,
The plating solution may further contain a conductive salt such as sodium hydrogen phosphate, potassium cyanide, potassium tartrate, sodium sulfate, or sodium citrate. Wherein the gold-palladium alloy plating solution for forming a PPF plating layer of a semiconductor lead frame is characterized in that it is a gold-palladium alloy plating solution.
The method according to claim 1,
Potassium hydrogen, sodium hydrogen, potassium carbonate, lactic acid, malic acid, or sodium gluconate are added to the plating solution. Wherein the copper foil is a gold-palladium alloy plating liquid for forming a PPF plating layer of a semiconductor lead frame.
The method according to claim 1,
Wherein the plating solution further comprises a chelating agent sodium-EDTA, nitrilo triacetic acid, or polyimide. The ultra-thin gold-palladium alloy for forming a PPF plating layer of a semiconductor lead frame Plating solution.
The method according to claim 1,
Wherein the plating solution further comprises a stabilizer Glycine, Glycerin, Phosphoric acid or Boric acid as a stabilizer.
The method according to claim 1,
The plating solution may contain at least one selected from the group consisting of polyethylene glycol tert-octyl phenyl ether, alkyl diaryl ether disulfonate sodium salt, ethylenediamine, polyethylene glycol, polyethylene glycol, glycol sulfuric acid) for forming a PPF plating layer of a semiconductor lead frame.