Abstract of the Disclosure

Before metalizing a silicon base semiconductor slice in an electroless plating bath, glassy phosphosilicate and glassy borosilicate layers that form on opposite sides of the slice during thermal diffusion must be removed. A known method of removing the glassy layers is the immersion of the slice in hydrofluoric acid; however, it is during the removal of the glassy layers that the surface underlying the glassy phosphosilicate is rendered passive for subsequent electroless deposition of a metal. In order to eliminate this passive condition and present an active surface that will receive a uniform and adherene plating of metal, the slice is immersed in a hot aqueous ammonium hydroxide solution after the removal of the glassy and prior to the metal plating

• flow diagram for processes disclosed in this invention.

 Citations [54]:
  
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