Ion implantation with molecular ions containing phosphorus and arsenic
View Patent ↗An ion implantation device and a method of manufacturing a semiconductor device is described, wherein ionized phosphorus-containing molecular clusters are implanted to form N-type transistor structures. The clusters are implanted to provide N-type doping for Source and Drain structures and Pocket or Halo formation, and for counter-doping Poly gates. These doping steps are critical to the formation of NMOS transistors. The molecular cluster ions have the chemical form AnHx + , or AnRHx + , where n and x are integers with 4<n and x≧0, and A is either As or P, and R is a molecule not containing phosphorus or arsenic, which is not injurious to the implantation process.
1. A method of implanting ions comprising:
(a) producing a volume of gas phase molecules of material of the form A n H x or A n RH x , wherein n and x are integers, and 4<n, and x>0; “A” denotes phosphorus and “R” designating a molecule not containing phosphorus , and which is not injurious to the method of implanting ions;
(b) ionizing the A n H X or A n RH X molecules to form A n H y + , A n H y − , A n RH y + ; or A n RH y − , wherein y is an integer such that y>0, thereby forming ionized molecules; and
(c) accelerating the ionized molecules by an electric field into a target.
2. The method as recited in claim 1 , in which the volume of gas phase molecules of (a) comprises Heptaphosphane, P 7 H 3 .
3. The method as recited in claim 1 , in which the volume of gas phase molecules of (a) comprises Cyclopentaphosphane, P 5 H 5 .
4. The method as recited in claim 1 , in which the volume of gas phase molecules of (a) comprises Tetra-tertbutylhexaphosphane.
5. The method as recited in claim 1 , in which the volume of gas phase molecules of (a) comprises Pentamethylheptaphosphane.
6. The method as recited in claim 1 , wherein step (b) comprises:
(b) ionizing the A n H X or A n RH X molecules by direct electron impact to form A n H y + , A n H y − , A n RH y + ; or A n RH y − , wherein y is an integer such that y>0.
7. The method as recited in claim 1 , wherein step (b) comprises:
(b) ionizing the A n H X or A n RH X molecules by creating a plasma to form A n H y + , A n H y − , A n RH y + ; or A n RH y − , wherein y is a an integer such that y>0.
8. The method as recited in claim 1 , wherein step (b) comprises:
(b) ionizing the A n H X or A n RH X molecules by way of an arc discharge to form A n H y + , A n H Y − , A n RH y + ; or A n RH y − , wherein y is an integer such that y>0.
9. A method of implanting ions comprising:
(a) producing a volume of gas phase molecules of material having a form A n H x or A n RH x , wherein n and x are integers, and 4<n, and x≧0; “A” denotes phosphorus, and “R” designating a molecule not containing phosphorus, and which is not injurious to the method of implanting ions;
(b) forming a plasma containing A n H x or A n RH x molecules, A n H y + , A n H y − , A n RH y + ; or A n RH y − ions, wherein y is a an integer such that y>0, and electrons; and
(c) accelerating a portion of said ions by an electric field to implant into a target, to perform doping of a semiconductor.
10. A method for forming a metal oxide semiconductor (MOS) device having a substrate, the method comprising:
(a) forming a well and opposing trench isolations in a first region of said substrate;
(b) forming a gate stack on said substrate between said opposing trench isolations defining exposed portions of said substrate; (a) and (b) defining a formation comprising:
(i) depositing or growing a gate dielectric;
(ii) depositing a polysilicon gate electrode, and
(iii) patterning to form the gate stack;
(c) depositing a pad oxide onto said exposed portions of said substrate and on top of said gate stack;
(d) implanting P 7 H x + ions to form drain extensions between said gate stack and said opposing trench isolations;
(e) forming spacers adjacent said gate stack;
(f) implanting N-type cluster ions to form source and drain regions;
(g) providing heat treatment to activate material implanted by step (d), thereby forming an N-type metal oxide semiconductor (MOS) device (NMOS).
11. The method as recited in claim 10 , further including:
(a) isolating first and second regions on said substrate;
(b) forming said NMOS device in a first region; and
(c) forming a PMOS device in a second region.
12. The method as recited in claim 11 wherein step (c) includes implanting P-type cluster ions in said second region.
13. The method as recited in claim 12 , wherein said P-type cluster ions are B 18 H x + or B 18 H x − , where 0≦x≦6.
14. A method of implanting ions comprising:
(a) producing a volume of gas phase molecules which includes P 7 H 3 ;
(b) ionizing said volume of gas phase molecules creating a plurality of ions having different masses;
(c) selecting one of said plurality of ions by mass defining a selected ion; and
(d) implanting said selected ion into a target.
15. The method as recited in claim 14 , wherein steps (c) and (d) comprise:
(c) selecting P 7 H 3 + ions; and
(d) implanting said P 7 H 3 + ions into the target.
16. The method as recited in claim 14 , wherein steps (c) and (d) comprise:
(c) selecting P 7 H 3 − ions; and
(d) implanting said P 7 H 3 − ions into the target.
17. A method for forming a semiconductor device comprising:
(a) generating molecular donor ions of the form A n H y + , A n H y − , A n RH y + , or A n RH y − , wherein n and y are integers, and 4<n, and y>0; “A” denotes phosphorus , and “R” designating a molecule not containing phosphorus, and which is not injurious to the method;
(b) implanting said molecular donor ions into a target forming an N-type region in said target;
(c) generating P-type ions;
(d) implanting said P-type ions in said target adjacent said N-type region forming a P-type region.
18. The method as recited in claim 17 , wherein step (c) and (d) comprise:
(c) generating molecular P-type ions; and
(d) implanting said P-type molecular ions in said target adjacent said N-type region to form the P-type region.
19. The method as recited in claim 17 , wherein step (c) and (d) comprise:
(c) generating P-type cluster ions; and
(d) implanting said P-type cluster ions in said target adjacent said N-type region to form the P-type region.
20. The method as recited in claim 19 , wherein step (c) and (d) comprise:
(c) generating B 18 H x + ions; and
(d) implanting said B 18 H x + ions in said target adjacent said N-type region forming a P-type region.
21. A method of implanting ions comprising:
(a) producing a volume of gas phase molecules of material having a form A n H x or A n RH x , wherein n and x are integers, and, 4<n, and x≧0; “A” denotes arsenic, and “R” designating a molecule not containing arsenic, and which is not injurious to the method;
(b) ionizing the A n H X or A n RH X molecules to form A n H y + , A n H Y − , A n RH y + ; or A n RH y − , wherein y is an integer such that y>0, thereby forming ionized molecules ; and
(c) accelerating the ionized molecules by an electric field into a target.
22. The method as recited in claim 21 , in which the volume of gas molecules of (a) comprise As 7 H 3 .
23. The method as recited in claim 21 , in which the volume of gas molecules of (a) comprises As 5 H 5 .
24. A method of implanting ions comprising:
(d) producing a volume of gas phase molecules of material having a form A n H x , or A n RH x , wherein n and x are integers, and 4<n and x≧0; “A” denotes—arsenic, and “R” designating a molecule not containing arsenic, and which is not injurious to the method;
(e) forming a plasma containing A n H X or A n RH X molecules, A n H y + , A n H Y − , A n RH y + , or A n RH y − ions , wherein y is an integer such that y>0, and electrons; and
(f) accelerating a portion of said ions by an electric field to implant into a target, to perform doping of a semiconductor.
25. A method for forming a metal oxide semiconductor (MOS) device having a substrate, the method comprising:
(g) forming a well and opposing trench isolations in a first region of said substrate;
(h) forming a gate stack on said substrate between said opposing trench isolations defining exposed portions of said substrate; said formation comprising:
(i) depositing or growing a gate dielectric;
(ii) depositing a polysilicon gate electrode, and
(iii) patterning to form the gate stack;
(i) depositing a pad oxide onto said exposed portions of said substrate and on top of said gate stack;
(j) implanting As 7 H x + ions to form drain extensions between said gate stack and said opposing trench isolations;
(k) forming spacers adjacent said gate stack;
(l) implanting N-type cluster ions to form source and drain regions;
(m) providing heat treatment to activate material implanted by step (d), thereby forming an N-type metal oxide semiconductor (MOS) device (NMOS).
26. The method as recited in claim 25 , further including the steps of:
(a) isolating first and second regions on said substrate;
(b) forming said NMOS device in a first region; and
(c) forming a PMOS device in a second region.
27. The method as recited in claim 26 wherein step (c) includes implanting P-type cluster ions in said second region.
28. The method as recited in claim 27 , wherein said P-type cluster ions are B 18 H x + or B 18 H x 31 , where 0≦x≦6.
29. A method for forming a semiconductor device comprising:
(a) generating molecular donor ions having a form A n H y + , A n H Y − , A n RH y + , or A n RH y − ,, wherein n and y are integers, and, 4<n, and x≧0; “A” denotes arsenic, and “R” designating a molecule not containing arsenic, and which is not injurious to the method;
(b) implanting said molecular donor ions into a target forming an N-type region in said target;
(c) generating P-type ions;
(d) implanting said P-type ions in said target adjacent said N-type region forming a P-type region.
30. The method as recited in claim 29 , wherein step (c) and (d) comprise:
(c) generating molecular P-type ions; and
(d) implanting said P-type molecular ions in said target adjacent said N-type region forming a P-type region.
31. The method as recited in claim 29 , wherein step (c) and (d) comprise:
(c) generating P-type cluster ions; and
(d) implanting said P-type cluster ions in said target adjacent said N-type region to form the P-type region.
32. The method as recited in claim 31 , wherein step (c) and (d) comprise:
(c) generating B 18 H x + ions; and
(d) implanting said B 18 H x + ions in said target adjacent said N-type region to form the P-type region.
33. The method as recited in claim 29 , wherein step (b) comprises:
(b) ionizing the A n H X or A n RH X molecules by direct etectron impact to form A n H y + , A n H y − , A n RH y + , or A n RH y − , wherein y is an integer such that y>0.
34. The method as recited in claim 29 , wherein step (b) comprises:
(b) ionizing the A n H X or A n RH X molecules by creating a plasma to form A n H y + , A n H y − , A n RH y + , or A n RH y − , wherein y is an integer such that y>0.
35. The method as recited in claims 29 , wherein step (b) comprises:
(b) ionizing the A n H X or A n RH X molecules by way of an arc discharge to form A n H y + , A n H y − , A n RH y + , or A n RH y − , wherein y is an integer such that y>0.