Title: Method of manufacturing a semiconductor device
Abstract: A method of producing a semiconductor device which removes catalyst elements from a silicon-containing semiconductor film while maintaining the advantage of low temperature process is provided. The method comprises the steps of: forming an amorphous semiconductor film containing silicon on a glass substrate to crystallize it by using a catalyst element; selectively introducing into the amorphous semiconductor film an impurity belonging to Group 15 to form gettering regions and regions to be gettered; and causing the catalyst element in the silicon film to move to the gettering regions by heat treatment. Through the gettering process, the crystalline silicon film can be obtained in which the concentration of nickel contained therein is sufficiently reduced.
Patent Number: 6,893,503 Issued on 05/17/2005 to Ohnuma, et al.
| Inventors:
|
Ohnuma; Hideto (Kanagawa, JP);
Yamazaki; Shunpei (Tokyo, JP);
Nakajima; Setsuo (Kanagawa, JP);
Ohtani; Hisashi (Kanagawa, JP)
|
| Assignee:
|
Semiconductor Energy Laboratory Co., Ltd. (Atsugi, JP)
|
| Appl. No.:
|
050182 |
| Filed:
|
March 26, 1998 |
Foreign Application Priority Data
| Current U.S. Class: |
117/94; 117/95; 117/97; 117/101; 117/102; 117/106 |
| Intern'l Class: |
C30B 025/04 |
| Field of Search: |
117/94,106,95,97,101,102
|
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Primary Examiner: Kunemund; Robert
Attorney, Agent or Firm: Fish & Richardson P.C.
Claims
1. A method of manufacturing a semiconductor device including at least a thin
film transistor, said method comprising the steps of:
forming an amorphous semiconductor film comprising silicon over a substrate having
an insulating surface;
providing the amorphous semiconductor film with an element which promotes crystallization
of the amorphous semiconductor film;
crystallizing the amorphous semiconductor film by a first heat treatment to form
a crystalline semiconductor film;
introducing an impurity element belonging to Group 15 into a first portion of
the crystalline semiconductor film by using a mask while a second portion of the
crystalline semiconductor film below the mask is not provided with the impurity
element;
wherein the first and second portions of the crystalline semiconductor film are
in contact with the insulating surface over the substrate;
performing a second heat treatment for gettering so that the element contained
in the second portion is moved to the first portion in a direction parallel to
the insulating surface; and
patterning the crystallized semiconductor film to form a crystalline semiconductor
island in the second portion thereby removing the first portion of the crystalline
semiconductor film;
forming an active layer of the thin film transistor using the crystalline semiconductor
island;
wherein the second heat treatment is performed in a temperature range not exceeding
a glass transition point of the substrate.
2. A method according to claim 1, wherein the crystalline semiconductor film
has grain boundaries.
3. A method according to claim 1, wherein the second heat treatment is performed
in the temperature range from 500 to 700° C.
4. A method according to claim 1, wherein the substrate is a glass substrate.
5. A method according to claim 1, wherein the second heat treatment is furnace annealing.
6. A method according to claim 1, wherein the amorphous semiconductor film comprises germanium.
7. A method according to claim 1, wherein the element which promotes crystallization
is at least one element selected from the group of elements consisting of Ni, Co,
Fe, Pd, Pt, Cu and Au.
8. A method according to claim 1, wherein the impurity element belonging to Group
15 is at least one element selected from the group of elements consisting of P,
N, As, Sb, and Bi.
9. A method of manufacturing a semiconductor device including at least a thin
film transistor, said method comprising the steps of:
forming an amorphous semiconductor film comprising silicon over a substrate having
an insulating surface;
selectively providing a first portion of the amorphous semiconductor film with
an element which promotes crystallization of the amorphous semiconductor film;
crystallizing the amorphous semiconductor film by a first heat treatment to form
a crystalline semiconductor film, so that a crystallization proceeds from the first
portion in a lateral direction to the insulating surface;
introducing an impurity element belonging to Group 15 into a second portion of
the crystalline semiconductor film by using a mask while a third portion of the
crystalline semiconductor film below the mask is not provided with the impurity
element;
wherein the second and third portions of the crystalline semiconductor film are
in contact with the insulating surface over the substrate;
performing a second heat treatment for gettering so that the element contained
in the third portion is moved to the second portion in a lateral direction to the
insulating surface; and
patterning the crystalline semiconductor film to form a crystalline semiconductor
island in the third portion thereby removing the second portion of the crystalline
semiconductor film;
forming an active layer of the thin film transistor using the crystalline semiconductor
island;
wherein the second heat treatment is performed in a temperature range not exceeding
a glass transition point of the substrate.
10. A method according to claim 9, wherein the crystalline semiconductor film
has grain boundaries.
11. A method according to claim 9, wherein the second heat treatment is performed
in the temperature range from 500 to 700° C.
12. A method according to claim 9, wherein the substrate is a glass substrate.
13. A method according to claim 9, wherein the second heat treatment is furnace annealing.
14. A method according to claim 9, wherein the amorphous semiconductor film comprises germanium.
15. A method according to claim 9, wherein the element which promotes crystallization
is at least one element selected from the group of elements consisting of Ni, Co,
Fe, Pd, Pt, Cu and Au.
16. A method according to claim 9, wherein the impurity element belonging to
Group 15 is at least one element selected from the group of elements consisting
of P, N, As, Sb, and Bi.
17. A method of manufacturing a semiconductor device including at least a thin
film transistor, said method comprising the steps of:
forming an amorphous semiconductor film comprising silicon over a substrate having
an insulating surface;
providing the amorphous semiconductor film with an element which promotes crystallization
of the amorphous semiconductor film;
crystallizing the amorphous semiconductor film by a first heat treatment to form
a crystalline semiconductor film;
irradiating a laser light or an intense light to the crystalline semiconductor
film;
introducing an impurity element belonging to Group 15 into a first portion of
the crystalline semiconductor film by using a mask after the irradiating step,
while a second portion of the crystalline semiconductor film below the mask is
not provided with the impurity element;
wherein the first and second portions of the crystalline semiconductor film are
in contact with the insulating surface over the substrate;
performing a second heat treatment for gettering so that the element contained
in the second portion is moved to the first portion in a lateral direction to the
insulating surface;
patterning the crystalline semiconductor film to form a crystalline semiconductor
island in the second portion thereby removing the first portion of the crystalline
semiconductor film;
forming an active layer of the thin film transistor using the crystalline semiconductor
island;
wherein the second heat treatment is performed in a temperature range not exceeding
a glass transition point of the substrate.
18. A method according to claim 17, wherein the crystalline semiconductor film
has grain boundaries.
19. A method according to claim 17, wherein the second heat treatment is performed
in the temperature range from 500 to 700° C.
20. A method according to claim 17, wherein the substrate is a glass substrate.
21. A method according to claim 17, wherein the second heat treatment is furnace annealing.
22. A method according to claim 17, wherein the amorphous semiconductor film
comprises germanium.
23. A method according to claim 17, wherein the element which promotes crystallization
is at least one element selected from the group of elements consisting of Ni, Co,
Fe, Pd, Pt, Cu and Au.
24. A method according to claim 17, wherein the impurity element belonging to
Group 15 is at least one element selected from the group of elements consisting
of P, N, As, Sb, and Bi.
25. A method of manufacturing a semiconductor device including at least a thin
film transistor, said method comprising the steps of:
forming an amorphous semiconductor film comprising silicon over a substrate having
an insulating surface;
selectively providing a first portion of the amorphous semiconductor film with
an element which promotes crystallization of the amorphous semiconductor film;
crystallizing the amorphous semiconductor film by a first heat treatment to form
a crystalline semiconductor film, so that a crystallization proceeds from the first
portion of the amorphous semiconductor film in a lateral direction to the insulating
surface;
irradiating a laser light or an intense light to the crystalline semiconductor
film;
introducing an impurity element belonging to Group 15 into a second portion of
the crystalline semiconductor film by using a mask after the irradiating step,
while a third portion of the crystalline semiconductor film below the mask is not
introduced with the impurity element;
wherein the second and third portions of the crystalline semiconductor film are
in contact with the insulating surface over the substrate;
performing a second heat treatment for gettering so that the element contained
in the third portion is moved to the second portion in a lateral direction to the
insulating surface;
patterning the crystalline semiconductor film to form a crystalline semiconductor
island in the third portion thereby removing the second portion of the crystalline
semiconductor film;
forming an active layer of the thin film transistor using the crystalline semiconductor
island;
wherein the second heat treatment is performed in the temperature range not exceeding
a glass transition point of the substrate.
26. A method according to claim 25, wherein the crystalline semiconductor film
has grain boundaries.
27. A method according to claim 25, wherein the second heat treatment is performed
in the temperature range from 500 to 700° C.
28. A method according to claim 25, wherein the substrate is a glass substrate.
29. A method according to claim 25, wherein the second heat treatment is furnace annealing.
30. A method according to claim 25, wherein amorphous semiconductor film comprises germanium.
31. A method according to claim 25, wherein the element which promotes crystallization
is at least one element selected from the group of elements consisting of Ni, Co,
Fe, Pd, Pt, Cu and Au.
32. A method according to claim 25, wherein the impurity element belonging to
Group 15 is at least one element selected from the group of elements consisting
of P, N, As, Sb, and Bi.
33. A method according to claim 1, wherein said step of introducing the impurity
element belonging to Group 15 is performed by plasma doping.
34. A method according to claim 8, wherein a dose of said phosphorous (P) is
set in a range from 1×10
13 ions/cm
2 to 5×10
14 ions/cm
2.
35. A method according to claim 8, wherein a concentration of said phosphorous
is a digit higher than a concentration of said element which promotes crystallization.
36. A method according to claim 9, wherein said step of introducing the impurity
element belonging to Group 15 is performed by plasma doping.
37. A method according to claim 16, wherein a dose of said phosphorous is set
in a range from 1×10
13 ions/cm
2 to 5×10
14 ions/cm
2.
38. A method according to claim 16, wherein a concentration of said phosphorous
is a digit higher than a concentration of said element which promotes crystallization.
39. A method according to claim 17, wherein said step of introducing the impurity
element belonging to Group 15 is performed by plasma doping.
40. A method according to claim 24, wherein a dose of said phosphorous is set
in a range from 1×10
13 ions/cm
2 to 5×10
14 ions/cm
2.
41. A method according to claim 24, wherein a concentration of said phosphorus
is a digit higher than a concentration of said element which promotes crystallization.
42. A method according to claim 25, wherein said step of introducing the impurity
element belonging to Group 15 is performed by plasma doping.
43. A method according to claim 32, wherein a dose of said phosphorous is set
in a range from 1×10
13 ions/cm
2 to 5×10
14 ions/cm
2.
44. A method according to claim 32, wherein a concentration of said phosphorous
is a digit higher than a concentration of said element which promotes crystallization.
45. A method of manufacturing a semiconductor device including at least a thin
film transistor, said method comprising the steps of:
forming an amorphous semiconductor film comprising silicon over a substrate having
an insulating surface;
providing the amorphous semiconductor film with an element which promotes crystallization
of the amorphous semiconductor film;
crystallizing the amorphous semiconductor film by a first heat treatment to form
a crystalline semiconductor film;
introducing an impurity element belonging to Group 15 into a first portion of
the crystalline semiconductor film by using a mask while a second portion of the
crystalline semiconductor film below the mask is not provided with the impurity
element;
wherein the first and second portions of the crystalline semiconductor film are
in contact with the insulating surface over the substrate;
performing a second heat treatment for gettering so that the element contained
in the second portion is moved to the first portion in a lateral direction to the
insulating surface;
patterning the crystalline semiconductor film to form a crystalline semiconductor
island in the second portion thereby removing the first portion of the crystalline
semiconductor film;
forming a gate insulating film over the crystalline semiconductor island;
forming at least one gate electrode comprising a metal on the gate insulating
film;
doping an impurity element into at least a second portion of the crystalline
semiconductor island to form a lightly doped drain region; and
forming at least a source region and a drain region by doping an impurity element
into third portions of the crystalline semiconductor island;
wherein the second heat treatment is performed in a temperature range not exceeding
a glass transition point of the substrate.
46. A method according to claim 45, wherein the second heat treatment is performed
in the temperature range from 500 to 700° C.
47. A method according to claim 45, wherein the element which promotes crystallization
is at least one element selected from the group of elements consisting of Ni, Co,
Fe, Pd, Pt, Cu and Au.
48. A method according to claim 45, wherein the impurity element belonging to
Group 15 is at least one element selected from the group of elements consisting
of P, N, As, Sb, and Bi.
49. A method according to claim 45, wherein said step of introducing the impurity
element belonging to Group 15 is performed by plasma doping.
50. A method according to claim 48, wherein a dose of said phosphorus is set
in a range from 1×10
13 ions/cm
2 to 5×10
14 ions/cm
2.
51. A method according to claim 48, wherein a concentration of said phosphorous
is a digit higher than a concentration of said element which promotes crystallization.
52. A method of manufacturing a semiconductor device including at least a thin
film transistor, said method comprising the steps of:
forming an amorphous semiconductor film comprising silicon over a substrate having
an insulating surface;
providing the amorphous semiconductor film with an element which promotes crystallization
of the amorphous semiconductor film;
crystallizing the amorphous semiconductor film by a first heat treatment to form
a crystalline semiconductor film;
introducing an impurity element belonging to Group 15 into a first portion of
the crystalline semiconductor film by using a mask while a second portion of the
crystalline semiconductor film below the mask is not provided with the impurity
element;
performing a second heat treatment for gettering so that the element contained
in the second portion is moved to the first portion in a lateral direction to the
insulating surface;
patterning the crystalline semiconductor film to form a crystalline semiconductor
island in the second portion thereby removing the first portion of the crystalline
semiconductor film;
forming a gate insulating film over the crystalline semiconductor island;
forming at least one gate electrode comprising a metal on the gate insulating
film;
doping an impurity element into at least a second portion of the crystalline
semiconductor island to form a lightly doped drain region;
forming at least a source region and a drain region by doping an impurity element
into third portions of the crystalline semiconductor island;
forming an interlayer insulating film comprising silicon over the gate electrode;
forming an interlayer insulating film comprising an organic resin film over the
interlayer insulating film; and
forming a pixel electrode that is electrically connected to the source region
or drain region through a contact hole over the interlayer film;
wherein the second heat treatment is performed in a temperature range not exceeding
a glass transition point of the substrate.
53. A method according to claim 52, wherein the second heat treatment is performed
in the temperature range from 500 to 700° C.
54. A method according to claim 52, wherein the amorphous semiconductor film
comprises germanium.
55. A method according to claim 52, wherein the element which promotes crystallization
is at least one element selected from the group of elements consisting of Ni, Co,
Fe, Pd, Pt, Cu and Au.
56. A method according to claim 52, wherein the impurity element belonging to
Group 15 is at least one element selected from the group of elements consisting
of P, N, As, Sb, and Bi.
57. A method according to claim 52, wherein said step of introducing the impurity
element belonging to Group 15 is performed by plasma doping.
58. A method according to claim 56, wherein a dose of said phosphorous is set
in a range from 1×10
13 ions/cm
2 to 5×10
14 ions/cm
2.
59. A method according to claim 56, wherein a concentration of said phosphorous
is a digit higher than a concentration of said element which promotes crystallization.
60. A method according to claim 45, wherein the amorphous semiconductor film
comprises germanium.
61. A method according to claim 1, wherein the element in the crystalline semiconductor
island after the second heat treatment has a concentration in a range of 1×10
18
atoms/cm
3 or lower.
62. A method according to claim 9, wherein the element in the crystalline semiconductor
island after the second heat treatment has a concentration in a range of 1×10
18
atoms/cm
3 or lower.
63. A method according to claim 17, wherein the element in the crystalline semiconductor
island after the second heat treatment has a concentration in a range of 1×10
18
atoms/cm
3 or lower.
64. A method according to claim 25, wherein the element in the crystalline semiconductor
island after the second heat treatment has a concentration in a range of 1×10
18
atoms/cm
3 or lower.
65. A method according to claim 45, wherein the element in the crystalline semiconductor
island after the second heat treatment has a concentration in a range of 1×10
18
atoms/cm
3 or lower.
66. A method according to claim 52, wherein the element in the crystalline semiconductor
island after the second heat treatment has a concentration in a range of 1×10
18
atoms/cm
3 or lower.
67. A method of manufacturing a semiconductor device including at least a thin
film transistor, said method comprising the steps of:
forming an amorphous semiconductor film on an insulating surface;
providing the amorphous semiconductor film with an element which promotes crystallization
of the amorphous semiconductor film;
performing a first heat treatment to crystallize the amorphous semiconductor
film;
introducing an impurity element belonging to Group 15 into a first portion of
the crystalline semiconductor film by using a mask while a second portion of the
crystalline semiconductor film below the mask is not provided with the impurity
element;
wherein the first and second portions of the crystalline semiconductor film are
in contact with the insulating surface over the substrate;
performing a second heat treatment for gettering so that the element contained
in the first portion is moved to the second portion in a direction parallel to
the insulating surface;
patterning the crystallized semiconductor film to form a crystalline semiconductor
island in the second portion thereby removing the first portion of the crystalline
semiconductor film; and
forming an active layer of the thin film transistor using the crystalline semiconductor
island.
68. A method according to claim 67, herein the crystalline inductor film has
grain boundaries.
69. A method according to claim 67, wherein the second heat treatment is performed
in the temperature range from 500 to 700° C.
70. A method according to claim 67, wherein the second heat treatment is furnace annealing.
71. A method according to claim 67, wherein the element which promotes crystallization
is at least one element selected from the group of elements consisting of Ni, Co,
Fe, Pd, Pt, Cu and Au.
72. A method according to claim 67, wherein the impurity element belonging to
Group 15 is at least one element selected from the group of elements consisting
of P, N, As, Sb, and Bi.
73. A method of manufacturing a semiconductor device including at least a thin
film transistor, said method comprising the steps of:
forming an amorphous semiconductor film on an insulating surface;
providing the amorphous semiconductor film with an element which promotes crystallization
of the amorphous semiconductor film;
performing a first heat treatment to crystallize the amorphous semiconductor;
irradiating a laser light or an intense light to the crystalline semiconductor
film;
introducing an impurity element belonging to Group 15 into a first portion of
the crystalline semiconductor film by using a mask after the irradiating step,
while a second portion of the crystalline semiconductor film below the mask is
not provided with the impurity element;
wherein the first and second portions of the crystalline semiconductor film are
in contact with the insulating surface over the substrate;
performing a second heat treatment for gettering so that the element contained
in the second portion is moved to the first portion in a lateral direction to the
insulating surface;
patterning the crystalline semiconductor film to form a crystalline semiconductor
island in the second portion thereby removing the first portion of the crystalline
semiconductor film; and
forming an active layer of the thin film transistor using the crystalline semiconductor
island.
74. A method according to claim 73, wherein the crystalline semiconductor film
has grain boundaries.
75. A method according to claim 73, wherein the second heat treatment is performed
in the temperature range from 500 to 700° C.
76. A method according to claim 73, wherein the second heat treatment is furnace annealing.
77. A method according to claim 73, wherein the element which promotes crystallization
is at least one element selected from the group of elements consisting of Ni, Co,
Fe, Pd, Pt, Cu and Au.
78. A method according to claim 73, wherein the impurity element belonging to
Group 15 is at least one element selected from the group of elements consisting
of P, N, As, Sb, and Bi.
79. A method of manufacturing a semiconductor device including at least a thin
film transistor, said method comprising the steps of:
forming an amorphous semiconductor film on an insulating surface;
providing the amorphous semiconductor film with an element which promotes crystallization
of the amorphous semiconductor film;
performing a first heat treatment to crystallize the amorphous semiconductor
film;
introducing an impurity element belonging to Group 15 into a first portion of
the crystalline semiconductor film by using a mask while a second portion of the
crystalline semiconductor film below the mask is not provided with the impurity
element;
wherein the first and second portions of the crystalline semiconductor film are
in contact with the insulating surface over the substrate;
performing a second heat treatment for gettering so that the element contained
in the second portion is moved to the first portion in a direction parallel to
the insulating surface;
forming a crystalline semiconductor island by removing the first portion and
a part of the second portion; and
forming an active layer of the thin film transistor using the crystalline semiconductor
island.
80. A method according to claim 79, wherein the crystalline semiconductor film
has grain boundaries.
81. A method according to claim 79, wherein the second heat treatment is performed
in the temperature range from 500 to 700° C.
82. A method according to claim 79, wherein the second heat treatment is furnace annealing.
83. A method according to claim 79, wherein the element which promotes crystallization
is at least one element selected from the group of elements consisting of Ni, Co,
Fe, Pd, Pt, Cu and Au.
84. A method according to claim 79, wherein the impurity element belonging to
Group 15 is at least one element selected from the group of elements consisting
of P, N, As, Sb, and Bi.
85. A method of manufacturing a semiconductor device including at least a thin
film transistor, said method comprising the steps of:
forming an amorphous semiconductor film on an insulating surface;
providing the amorphous semiconductor film with an element which promotes crystallization
of the amorphous semiconductor film;
performing a first heat treatment to crystallize the amorphous semiconductor;
irradiating a laser light or an intense light to the crystalline semiconductor
film;
introducing an impurity element belonging to Group 15 into a first portion of
the crystalline semiconductor film by using a mask after the irradiating step,
while a second portion of the crystalline semiconductor film below the mask is
not provided with the impurity element;
wherein the first and second portions of the crystalline semiconductor film are
in contact with the insulating surface over the substrate;
performing a second heat treatment for gettering so that the element contained
in the second portion is moved to the first portion in a lateral direction to the
insulating surface;
forming a crystalline semiconductor island by removing the first portion and
a part of the second portion; and
forming an active layer of the thin film transistor using the crystalline semiconductor
island.
86. A method according to claim 85, wherein the crystalline semiconductor film
has grain boundaries.
87. A method according to claim 85, wherein the second heat treatment is performed
in the temperature range from 500 to 700° C.
88. A method according to claim 85, wherein the second heat treatment is furnace annealing.
89. A method according to claim 85, wherein the element which promotes crystallization
is at least one element selected from the group of elements consisting of Ni, Co,
Fe, Pd, Pt, Cu and Au.
90. A method according to claim 85, wherein the impurity element belonging to
Group 15 is at least one element selected from the group of elements consisting
of P, N, As, Sb, and Bi.
91. A method according to claim 1, wherein the element which promotes crystallization
is provided with the amorphous semiconductor layer by introducing into the amorphous
semiconductor film or applying a layer containing the element to the amorphous
semiconductor film.
92. A method according to claim 9, wherein the element which promotes crystallization
is provided with the amorphous semiconductor layer by introducing into the amorphous
semiconductor film or applying a layer containing the element to the amorphous
semiconductor film.
93. A method according to claim 17, wherein the element which promotes crystallization
is provided with the amorphous semiconductor layer by introducing into the amorphous
semiconductor film or applying a layer containing the element to the amorphous
semiconductor film.
94. A method according to claim 25, wherein the element which promotes crystallization
is provided with the amorphous semiconductor layer by introducing into the amorphous
semiconductor film or applying a layer containing the element to the amorphous
semiconductor film.
95. A method according to claim 45, wherein the element which promotes crystallization
is provided with the amorphous semiconductor layer by introducing into the amorphous
semiconductor film or applying a layer containing the element to the amorphous
semiconductor film.
96. A method according to claim 52, wherein the element which promotes crystallization
is provided with the amorphous semiconductor layer by introducing into the amorphous
semiconductor film or applying a layer containing the element to the amorphous
semiconductor film.
97. A method according to claim 67, wherein the element which promotes crystallization
is provided with the amorphous semiconductor layer by introducing into the amorphous
semiconductor film or applying a layer containing the element to the amorphous
semiconductor film.
98. A method according to claim 73, wherein the element which promotes crystallization
is provided with the amorphous semiconductor layer by introducing into the amorphous
semiconductor film or applying a layer containing the element to the amorphous
semiconductor film.
99. A method according to claim 79, wherein the element which promotes crystallization
is provided with the amorphous semiconductor layer by introducing into the amorphous
semiconductor film or applying a layer containing the element to the amorphous
semiconductor film.
100. A method according to claim 85, wherein the element which promotes crystallization
is provided with the amorphous semiconductor layer by introducing into the amorphous
semiconductor film or applying a layer containing the element to the amorphous
semiconductor film.
Description
