Method of forming semiconductor device
A semiconductor device may include, but is not limited to, first and second well regions, and a well isolation region isolating the first and second well regions. The first and second well regions each may include an active region, a device isolation groove that defines the active region, and a device isolation insulating film that fills the device isolation groove. The first and second well regions may include first and second well layers, respectively. The well isolation region may include a well isolation groove, a well isolation insulating film that fills the well isolation groove, and a diffusion stopper layer disposed under a bottom of the well isolation groove. The first and second well layers have first and second bottoms respectively, which are deeper in depth than a bottom of the device isolation groove and shallower in depth than the bottom of the well isolation groove.
1. A method of forming a semiconductor device comprising:
forming a device isolation groove in a semiconductor substrate, the device isolation groove defining an active region of the semiconductor substrate;
forming a device isolation insulating film that fills the device isolation groove;
forming a well isolation groove in the semiconductor substrate, the well isolation groove being deeper in depth than the device isolation groove;
forming a diffusion stopper layer under a bottom of the well isolation groove;
forming a well isolation insulating film that fills the well isolation groove;
selectively forming first and second well layers in the active region of the semiconductor substrate, the first and second well layers having first and second bottoms respectively, and the first and second bottoms being deeper in depth than a bottom of the device isolation groove and shallower in depth than the bottom of the well isolation groove.
2. The method according to claim 1 , wherein forming the well isolation insulating film comprises utilizing micro loading effect.
3. The method according to claim 1 , wherein forming the well isolation insulating film comprises a photolithography process.
4. The method according to claim 1 , wherein forming the diffusion stopper layer comprises introducing at least one of carbon, nitrogen, fluorine, and germanium into the semiconductor substrate under the well isolation groove.
5. The method according to claim 1 , further comprising:
forming an oxide film on a surface of the semiconductor substrate;
forming a nitride film on the oxide film; and
selectively removing the nitride film to form a nitride pattern, and
wherein forming the device isolation groove comprises carrying out a dry etching process using the nitride pattern as a mask.
6. The method according to claim 1 , wherein selectively forming the first and second well layers comprises:
selectively introducing first and second impurities into the active region of the semiconductor substrate at first and second depths, the first and second depths being deeper in depth than a bottom of the device isolation groove and shallower in depth than the bottom of the well isolation groove.
7. The method according to claim 6 , wherein selectively introducing the first and second impurities comprises:
carrying out a first ion-implantation process using a first mask for selectively introducing the first impurity; and
carrying out a second ion-implantation process using a second mask for selectively introducing the second impurity.
8. A method of forming a semiconductor device comprising:
forming a well isolation groove in a semiconductor substrate;
forming a diffusion stopper layer under a bottom of the well isolation groove;
forming a well isolation insulating film that fills the well isolation groove;
forming a device isolation groove in the semiconductor substrate, the device isolation groove defining an active region of the semiconductor substrate, the device isolation groove being shallower in depth than the well isolation groove;
forming a device isolation insulating film that fills the device isolation groove;
selectively forming first and second well layers in the active region of the semiconductor substrate, the first and second well layers having first and second bottoms respectively, and the first and second bottoms being deeper in depth than a bottom of the device isolation groove and shallower in depth than the bottom of the well isolation groove.
9. The method according to claim 8 , wherein forming the well isolation insulating film comprises utilizing micro loading effect.
10. The method according to claim 8 , wherein forming the well isolation insulating film comprises a photolithography process.
11. The method according to claim 8 , wherein forming the diffusion stopper layer comprises introducing at least one of carbon, nitrogen, fluorine, and germanium into the semiconductor substrate under the well isolation groove.
12. The method according to claim 8 , further comprising:
forming an oxide film on a surface of the semiconductor substrate;
forming a nitride film on the oxide film; and
selectively removing the nitride film to form a nitride pattern, and
wherein forming the well isolation groove comprises carrying out a dry etching process using the nitride pattern as a mask.
13. The method according to claim 8 , wherein selectively forming the first and second well layers comprises:
selectively introducing first and second impurities into the active region of the semiconductor substrate at first and second depths, the first and second depths being deeper in depth than a bottom of the device isolation groove and shallower in depth than the bottom of the well isolation groove.
14. The method according to claim 13 , wherein selectively introducing the first and second impurities comprises:
carrying out a first ion-implantation process using a first mask for selectively introducing the first impurity; and
carrying out a second ion-implantation process using a second mask for selectively introducing the second impurity.