Method for producing a vertical transistor component

• US 20060097312A1
• Filed: 09/30/2005
• Published: 05/11/2006
• Est. Priority Date: 09/30/2004
• Status: Active Grant

• Current Assignee: Infineon Technologies AG
• Original Assignee: Infineon Technologies AG
• Inventors: Rieger, Walter, Poelzl, Martin
• Granted Patent: US 7,767,527 B2
• Time in Patent Office: Days
• US Class Current: 257/328
• CPC Class Codes: H01L 29/0865 Disposition
• CPC Class Codes: H01L 29/0869 Shape cell layout H01L29/0696
• CPC Class Codes: H01L 29/407 Recessed field plates, e.g. trench field plates, buried field plates
• CPC Class Codes: H01L 29/66719 With a step of forming an insulating sidewall spacer
• CPC Class Codes: H01L 29/66734 with a step of recessing the gate electrode, e.g. to form a trench gate electrode
• CPC Class Codes: H01L 29/7805 in antiparallel, e.g. freewheel diode
• CPC Class Codes: H01L 29/7813 with trench gate electrode, e.g. UMOS transistors trench gate electrodes per se H01L29/4236

Abstract

The invention relates to a method for producing a vertical transistor component, having the following method steps of:

Providing a semiconductor substrate (100), applying an auxiliary layer (110) to the semiconductor substrate (100), patterning the auxiliary layer (110) for the purpose of producing at least one trench (114) which extends as far as the semiconductor substrate (100) and which has opposite sidewalls (115), producing a monocrystalline semiconductor layer (132) on at least one of the sidewalls (115) of the trench (114), producing an electrode (140) insulated from the monocrystalline semiconductor layer (132) on the at least one sidewall (115) of the trench (114) and the semiconductor substrate (100). The invention furthermore relates to a method for producing a vertical transistor component, having the following method steps of:

Providing a semiconductor substrate (200), applying an auxiliary layer (210) to the semiconductor substrate (200), patterning the auxiliary layer (210) for the purpose of producing at least one trench (214) which extends as far as the semiconductor substrate (200), producing a monocrystalline semiconductor zone (230) in the at least one trench (213), removing the auxiliary layer (210) at least in sections, producing an electrode (240) insulated from the monocrystalline semiconductor zone (230) and the semiconductor substrate.

Claims

1-32. -32. (canceled)

33. A method for producing a vertical transistor component, comprising:

a) providing a semiconductor substrate,

b) providing an auxiliary layer on the semiconductor substrate,

c) patterning the auxiliary layer such that at least a first trench is produced that extends as far as a surface of the semiconductor substrate, the first trench having opposite sidewalls,

d) producing a monocrystalline semiconductor layer on at least one of the sidewalls of the first trench, and

e) producing an electrode insulated from the monocrystalline semiconductor layer and the semiconductor substrate.

34. The method according to claim 33, wherein step d) further comprises:

applying an amorphous semiconductor layer,

recrystallizing the amorphous semiconductor layer by carrying out a thermal process.

35. The method according to claim 34, wherein the amorphous semiconductor layer is doped in situ with dopant atoms.

36. The method according to claim 33, further comprising etching back the auxiliary layer after step d), such that the monocrystalline semiconductor layer extends above the auxiliary layer on a side remote from the substrate.

37. The method according to claim 33, wherein step e) further comprises:

providing an insulation layer at least on that side of the monocrystalline semiconductor layer which faces the trench and on regions of the semiconductor substrate which are uncovered within the first trench, and

filling the first trench with an electrode material.

38. The method according to claim 37, further comprising applying a protective layer, in least in sections, on a side of the electrode remote from the substrate.

39. The method according to claim 38, further comprising removing the protective layer at least in sections above the electrode such that the electrode is contact-connectable in self-aligning fashion.

40. The method according to claim 33, wherein the first trench has at least one section in which a widened section of the electrode is formed, the electrode being contact-connectable at the widened section.

41. The method according to claim 33, wherein the semiconductor substrate is doped with dopant atoms of a first conduction type, and further comprising, in the monocrystalline semiconductor layer:

producing a first semiconductor zone of the first conduction type on a side of the first semiconductor zone remote from the substrate, and

producing a complementarily doped second semiconductor zone subsequent to said first semiconductor zone.

42. The method according to claim 41, wherein the first semiconductor zone is produced by implantation of dopant atoms and subsequent activation of the dopant atoms.

43. The method according to claim 41, wherein the second semiconductor zone is produced by implantation of dopant atoms and subsequent activation of the dopant atoms.

44. The method according to claim 41, wherein the second semiconductor zone is formed by a section having a basic doping of the monocrystalline semiconductor layer.

45. The method according to claim 41, wherein a third semiconductor zone of the first conduction type as the semiconductor substrate is produced in the monocrystalline semiconductor layer between the semiconductor substrate and the second semiconductor zone.

46. The method according to claim 45, wherein the third semiconductor zone is produced using a thermal step, the thermal step having a temperature and a duration chosen such that dopant atoms diffuse from the semiconductor substrate into the monocrystalline semiconductor layer.

47. The method according to claim 33, wherein the monocrystalline semiconductor layer is doped with dopant atoms of a same conduction type as the semiconductor substrate.

48. The method according to claim 33, further comprising introducing dopants into a section of the semiconductor substrate which extends into said semiconductor substrate and which is arranged on a side of the monocrystalline semiconductor layer that is remote from the electrode.

49. A method for producing a vertical transistor component, comprising:

a) providing a semiconductor substrate,

b) applying an auxiliary layer to the semiconductor substrate,

c) patterning the auxiliary layer to produce at least a first trench which extends to the semiconductor substrate,

d) producing a monocrystalline semiconductor zone in the first trench,

e) removing the auxiliary layer at least in sections,

f) producing an electrode insulated from the monocrystalline semiconductor zone and the semiconductor substrate.

50. The method according to claim 49, further comprising removal of the auxiliary layer such that the monocrystalline semiconductor zone is in pillar form, and wherein step f) further comprises:

producing an insulation layer on sidewalls of the monocrystalline semiconductor zone, and on the semiconductor substrate,

depositing an electrode material.

51. The method according to claim 49, further comprising:

providing an embedded electrode layer in the auxiliary layer in a manner spaced apart from the semiconductor substrate,

patterning the electrode layer together with the auxiliary layer,

removing the auxiliary layer before the production of the electrode only in regions above the electrode layer,

providing an insulation layer on the electrode layer before step f).

52. The method according to claim 49, wherein the monocrystalline semiconductor zone is doped complementarily with respect to the semiconductor substrate, and further comprising:

producing a first semiconductor zone of a same conduction type as the semiconductor substrate at an end of the monocrystalline semiconductor zone which is remote from the semiconductor substrate.

55. The method according to claim 52, further comprising producing, in the monocrystalline semiconductor zone adjacent to the semiconductor substrate, a second semiconductor zone of a same conduction type as the semiconductor substrate.

56. The method according to claim 55, wherein the second semiconductor zone is produced using a thermal step, the thermal step having a temperature and duration chosen such that dopant atoms diffuse from the semiconductor substrate into the monocrystalline semiconductor zone.

57. A vertical transistor component, having:

a semiconductor substrate,

a gate electrode disposed above the semiconductor substrate and insulated from the semiconductor substrate,

a monocrystalline semiconductor layer disposed adjacent to the gate electrode in a lateral direction and insulated from the gate electrode, the monocrystalline semiconductor layer extending in a vertical direction as far as the semiconductor substrate, and

a connection electrode, which is arranged adjacent to the monocrystalline semiconductor layer above the semiconductor substrate and which makes contact with the semiconductor substrate in a region of a semiconductor zone that is doped complementarily with respect to remaining regions of the semiconductor substrate.

58. The transistor component according to claim 57, further comprising an insulation layer configured to insulate the connection electrode from the monocrystalline semiconductor layer.

59. The transistor component according to claim 57, wherein the monocrystalline semiconductor layer has a body zone doped complementarily with respect to the semiconductor substrate and a source zone adjoining the body zone in the vertical direction of a same conduction type as the semiconductor substrate, and wherein the connection electrode short-circuits the source zone and the body zone.

60. The transistor component according to claim 59, wherein the monocrystalline semiconductor layer has a semiconductor zone of the same conductivity type as the semiconductor substrate, the semiconductor zone disposed between the semiconductor substrate and the body zone.

61. The transistor component according to claim 57, wherein the monocrystalline semiconductor layer extends beyond the gate electrode in the vertical direction.

62. The transistor component according to claim 57, wherein the gate electrode has a section in which the gate electrode is wider in comparison with remaining sections of the gate electrode.

63. The transistor component according to claim 57, wherein the semiconductor substrate has a more heavily doped section and a more weakly doped section, the more weakly doped section disposed adjacent to the gate electrode and the connection electrode.