A method with three embodiments of manufacturing metal lines and solder bumps using electroless deposition techniques. The first embodiment uses a PdSi x seed layer 50 for electroless deposition. The PdSi x layer 50 does not require activation. A metal line is formed on a barrier layer 20 and an adhesion layer 30. A Palladium silicide seed layer 50 is then formed and patterned. Ni, Pd or Cu is electroless deposited over the Palladium silicide layer 50 to form a metal line. The second embodiment selectively electrolessly deposits metal 140 over an Adhesion layer 130 composed of Poly Si, Al, or Ti. A photoresist pattern 132 is formed over the adhesion layer. A metal layer 140 of Cu or Ni is electrolessly deposited over the adhesion layer. The photoresist layer 132 is removed and the exposed portion of the adhesion layer 130 and the underlying barrier metal layer 120 are etched thereby forming a metal line. The third embodiment electroless deposits metal over a metal barrier layer that is roughen by chemical mechanical polishing. A solder bump is formed using an electroless deposition of Cu or Ni by: depositing an Al layer 220 and a barrier metal layer 230 over a substrate 10. The barrier layer 230 is polished and activated. Next, the aluminum layer 220 and the barrier metal layer 230 are patterned. A metal layer 240 is electroless deposited. Next a solder bump 250 is formed over the electroless metal layer 240.

Method of electroless plating copper on nitride barrier

To a neutral electroless gold plating bath comprising a gold sulfite, a sulfite, and a reducing agent, there are added an organic phosphonic acid or a salt thereof and an optional stabilizer in the form of a non-ionic surfactant or non-ionic polymer. A gold plating film having an aesthetic lemon yellow color tone and susceptible to bonding deposits on an article from the bath without attacking the base material of the article and without plating spread.

Electroless gold plating bath

A process is used to produce copper bumps on a semiconductor chip or a wafer containing several microchips. The chip or wafer has a layer incorporating a plurality semiconductor devices and a passivation layer having openings. Conductive pads within the openings are in contact with the semiconductor devices. In the process, a conductive adhesive material is deposited onto the conductive pads to form adhesion layers. A conductive metal is deposited onto the adhesion layers to form barrier layers and the passivation layer is subjected to an acid dip solution to remove particles of the conductive adhesive material which can be attached to the passivation layer. Copper is then deposited onto the barrier layers to form the copper bump. Each one of the deposition steps are performed electrolessly. Furthermore, plating solutions and a wafer and a microchip produced by the above process and are provided.

Wafer level electroless copper metallization and bumping process, and plating solutions for semiconductor wafer and microchip

The present invention provides an electroless gold plating solution which does not precipitate gold at high concentrations of thallium or lead compound, while retaining its effects such as increased deposition rate and larger crystallite sizes in the deposited layer. The electroless gold plating solution according to the invention contains 0.1-10 g/l of a chelating agent, such as diethylenetriaminepentaacetic acid (DTPA), ethylenediaminetetraacetic acid or nitrilotriacetic acid, DTPA being a preferable agent.

Electroless gold plating solution

Electroless gold plating baths and plating methods using these baths are provided. The electroless gold plating bath includes i) water-soluble gold compound, ii) complexing agent that stabilizes gold ions in the plating bath, but does not cause substantial dissolution of nickel, cobalt or palladium in the plating bath, and iii) a polyethyleneimine compound. When a material to be plated is subjected to such a gold plating bath, corrosion of the base metal under the surface of the material to be plated is reduced by controlling the substitution reaction rate immediately after initiation of the reaction, and adhesion between the base metal and deposited gold coating is increased.

Electroless gold plating bath and method

An electroless palladium plating composition which comprises (1) 0.001-0.1 mol/l of a palladium compound, (2) 0.01-1 mol/l of a hypophosphite compound, (3) 0.01-5 mol/l of at least one member selected from the group consisting of ammonia and alkylamine compounds, (4) 0.01-20 mg/l of high-molecular weight polyethyleneimine having molecular weight of 300 to 100000 and (5) 0.01-10 g/l of an aliphatic alkyenylamine, and which is used at a pH in the range of 5-10.

Electroless palladium plating composition

A process for electroless gold plating using plating solution comprizing cyanoaurate, alkaline cyanide, reducing agent, alkaline hydroxide, crystal condition controlling agent and stabilizer characterized in that an aldehyde or a ketone compound is added together with replenished gold salt, and hydrogen peroxide is also added, if necessary.

Process for electroless gold plating

PURPOSE:To provide an electroless palladium plating liquid which can be used in an industrial scale. CONSTITUTION:The plating bath is hydrophosphorus acid type containing (1) 0.001-0.1mol/l palladium compd., (2) at least one kind of hydrophosphite compd. by 0.01-1mol/l, and (3) at least one of ammonia and satd. alkylamine compd. by 0.01-5mol/l. To this plating bath, a polyethylene imine polymer having 300-100000mol.wt. and unsatd. alkyl amine are added by 0.01-20mg/l and 0.01-10g/l, respectively. Thereby, this plating liquid can be used for a long time only by replenishing the consumed components of the plating liquid such as palladium, reducing agent, etc.

Electroless palladium plating liquid

PURPOSE:To make it possible to continuously use an electroless gold plating soln. over a long period of time while maintaining a constant plating rate and uniformity of deposited films by keeping the concn. of cyanide ions in the plating soln. within a certain range without deteriorating the performance of the plating soln. CONSTITUTION:When electroless gold plating is carried out with a plating soln. contg. gold cyanide, alkali cyanide, a reducing agent, alkali hydroxide, a crystal regulating agent and a stabilizing agent, an aldehyde or ketone compd. is added at the time of replenishing gold cyanide.

Shigemitsu Kawagishi

Papers

Electroless palladium plating composition

Process for electroless gold plating

Electroless palladium plating liquid

Electroless gold plating method