Abstract of the Disclosure

A method of forming a high speed transistor by providing a mask on the surface of a semiconductor, the mask having an opening width of less than 4.45 multiples of an atom diffusion length of a given impurity of one conductivity type, exposing the surface through the opening to an atmosphere containing the given impurity to form a highly doped surface region, heating the substrate in an atmosphere having a lesser concentration of the given impurity to form a collector-base junction and forming by diffusion through the same opening an emitter-base junction.

• Figure 1 is a flow diagram illustrating a preferred process of the present invention.
• Figure 6 shows the temperature coefficient of resistance as a function of surface concentration for boron diffused resistors.
• Figure 7 is a series of curves showing junction depth as a function of mask opening width.

 Citations [54]:
  
2,873,222  02/1959  Derick
3,165,430  01/1965  Hugle
2,981,645  04/1961  Tucker
3,246,214  04/1966  Hugle
2,981,877  04/1961  Noyce
2,802,760  08/1957  Derick
3,006,789  10/1961  Nijland
3,025,589  03/1962  Hoerni