Manufacturing method for making bipolar device having double polysilicon structure

A manufacturing method for a semiconductor device, comprising the steps of:

• forming a conducting film on a semiconductor substrate;
• forming a first impurity diffused layer of a first conduction type in said semiconductor substrate by impurity diffusion from said conducting film;
• forming a first insulating film on said conducting film;
• forming a first hole through a laminated film composed of said first insulating film and said conducting film;
• forming a second impurity diffused layer of said first conduction type in said semiconductor substrate exposed to said first hole;
• forming a side wall from a second insulating film in said first hole to form a second hole;
• removing an entire portion of said second impurity diffused layer of said first conduction type vertically beneath said second hole;
• and
• forming a third impurity diffused layer of said first conduction type in said semiconductor substrate exposed to said second hole.

A manufacturing method for a semiconductor device, comprising the steps of:

• forming a first conducting film on a semiconductor substrate;
• forming a first impurity diffused layer of a first conduction type in said semiconductor substrate by impurity diffusion from said first conducting film;
• forming a first insulating film on said first conducting film;
• forming a first hole through a laminated film composed of said first insulating film and said first conducting film;
• forming a second impurity diffused layer of said first conduction type in said semiconductor substrate exposed to said first hole;
• forming a side wall from a second insulating film in said first hole to form a second hole;
• forming a second conducting film in said second hole;
• forming a third impurity diffused layer of said first conduction type in said semiconductor substrate by impurity diffusion from said second conducting film;
• and
• forming a fourth impurity diffused layer of a second conduction type in said third impurity diffused layer by impurity diffusion from said second conducting film.

A manufacturing method for a semiconductor device, comprising the steps of:

• forming a conducting film on a semiconductor substrate;
• forming a first impurity diffused layer of a first conduction type in said semiconductor substrate by impurity diffusion from said conducting film;
• forming a first insulating film on said conducting film;
• forming a first hole through a laminated film composed of said first insulating film and said conducting film;
• forming a second impurity diffused layer of said first conduction type in said semiconductor substrate exposed to said first hole;
• forming a side wall from a second insulating film in said first hole to form a second hole;
• removing a portion of said second impurity diffused layer exposed to said second hole;
• and
• forming a third impurity diffused layer of said first conduction type in said semiconductor substrate exposed to said second hole.

A manufacturing method for a semiconductor device, comprising the steps of:

• forming a first conducting film on a semiconductor substrate;
• forming a first impurity diffused layer of a first conduction type in said semiconductor substrate by impurity diffusion from said first conducting film;
• forming a first insulating film on said first conducting film;
• forming a first hole through a laminated film composed of said first insulating film and said first conducting film;
• forming a second impurity diffused layer of said first conduction type in said semiconductor substrate exposed to said first hole;
• forming a side wall from a second insulating film in said first hole to form a second hole;
• removing a portion of said second impurity diffused layer exposed to said second hole;
• forming a second conducting film in said second hole;
• forming a third impurity diffused layer of said first conduction type in said semiconductor substrate by impurity diffusion from said second conducting film;
• and
• forming a fourth impurity diffused layer of a second conduction type in said third impurity diffused layer by impurity diffusion from said second conducting film.

A manufacturing method for a semiconductor device, comprising the steps of:

• forming a first impurity diffused layer of a first conduction type in a semiconductor substrate;
• forming a conducting film connected to said first impurity diffused layer;
• forming a first insulating film on said conducting film;
• forming a first hole through a laminated film composed of said first insulating film and said conducting film;
• forming a second impurity diffused layer of said first conduction type in said semiconductor substrate exposed to said first hole;
• forming a side wall from a second insulating film in said first hole to form a second hole;
• forming a third insulating film in said second hole;
• and
• forming a third impurity diffused layer of said first conduction type in said semiconductor substrate exposed to said second hole.

A manufacturing method for a semiconductor device, comprising the steps of:

• forming a first impurity diffused layer of a first conduction type in a semiconductor substrate;
• forming a first conducting film connected to said first impurity diffused layer;
• forming a first insulating film on said first conducting film;
• forming a first hole through a laminated film composed of said first insulating film and said first conducting film;
• forming a second impurity diffused layer of said first conduction type in said semiconductor substrate exposed to said first hole;
• forming a side wall from a second insulating film in said first hole to form a second hole;
• removing an entire portion of said second impurity diffused layer of said first conduction type vertically beneath said second hole;
• forming a second conducting film in said second hole;
• and
• forming a third impurity diffused layer of said first conduction type in said semiconductor substrate exposed to said second hole.

A manufacturing method for a semiconductor device, comprising the steps of:

• forming a first impurity diffused layer of a first conduction type in a semiconductor substrate;
• forming a first conducting film connected to said first impurity diffused layer;
• forming a first insulating film on said first conducting film;
• forming a first hole through a laminated film composed of said first insulating film and said first conducting film;
• forming a second insulating film in said first hole;
• forming a second impurity diffused layer of said first conduction type in said semiconductor substrate exposed to said first hole;
• forming a side wall from a third insulating film in said first hole to form a second hole;
• forming a second conducting film in said second hole;
• and
• forming a third impurity diffused layer of a second conduction type in said second impurity diffused layer by impurity diffusion from said second conducting film.

A manufacturing method for a semiconductor device, comprising the steps of:

• forming a first impurity diffused layer of a first conduction type in a semiconductor substrate;
• forming a first conducting film connected to said first impurity diffused layer;
• forming a first insulating film on said first conducting film;
• forming a first hole through a laminated film composed of said first insulating film and said first conducting film;
• forming a second insulating film in said first hole;
• forming a second impurity diffused layer of said first conduction type in said semiconductor substrate exposed to said first hole;
• forming a side wall from a third insulating film in said first hole to form a second hole;
• forming a second conducting film in said second hole;
• forming a third impurity diffused layer of said first conduction type in said second impurity diffused layer by impurity diffusion from said second conducting film;
• and
• forming a fourth impurity diffused layer of a second conduction type in said third impurity diffused layer by impurity diffusion from said second conducting film.

A manufacturing method for a semiconductor device, comprising the steps of:

• forming a first impurity diffused layer of a first conduction type in a semiconductor substrate;
• forming a first conducting film connected to said first impurity diffused layer, said first conducting film comprising a polycrystalline film;
• increasing a crystal grain size in at least a part of said first conducting film such that the crystal grain size is in a range of from several tens of nanometers to several micrometers;
• forming a second conducting film on said first conducting film;
• forming a first insulating film on said second conducting film;
• forming a hole through a laminated film composed of said first insulating film, said first conducting film, and said second conducting film;
• forming a second insulating film in said hole;
• and
• forming a second impurity diffused layer of said first conduction type in said semiconductor substrate exposed to said hole.

A manufacturing method for a bipolar transistor comprising an impurity layer of a first conduction type formed in a semiconductor substrate;

• a first insulating film formed in contact with said impurity layer;
• a first conducting film of a first conduction type formed in contact with said first insulating film;
• a second insulating film formed in contact with said first conducting film;
• a second conducting film formed in a hole form through said insulating film said first conducting film and said second insulating film said conducting film connecting said first conducting film to said impurity layer and forming a base of said bipolar transistor;
• said manufacturing method comprising the steps of forming said second insulating film;
• forming said second conducting film on said second insulating film;
• forming a third insulating film on said second conducting film;
• removing said third insulating film except a portion thereof present on a side surface of said second conducting film in said hole by etch-back;
• flattening a surface of said semiconductor substrate;
• removing said second conducting film except a portion thereof present on a bottom surface and a side surface of said hole by etch-back so as to connect said second conducting film to said first conducting film.

A manufacturing method for a semiconductor device, comprising the steps of:

• forming a first insulating film on a semiconductor substrate;
• forming a first conducting film on said first insulating film;
• forming a second insulating film on said first conducting film;
• forming a first hole through a laminated film composed of said first insulating film, said first conducting film, and said second insulating film;
• forming a second conducting film on a wall of said first hole;
• forming a third insulating film in said first hole;
• forming an impurity diffused layer of a first conduction type in said semiconductor substrate exposed to said first hole;
• forming a side wall from a fourth insulating film in said first hole to form a second hole;
• and
• removing a portion of the semiconductor substrate forming a link base in a base forming region through said second hole.