Methods of incorporating germanium within CMOS process
View Patent ↗Methods for deposition of a Ge layer during a CMOS process on a monolithic device are disclosed. The insertion of the Ge layer enables the conversion of light to electrical signals easily. As a result of this method, standard metals can be attached directly to the Ge in completing an electrical circuit. Vias can also be used to connect to the Ge layer. In a first aspect of the invention, a method comprises the step of incorporating the deposition of Ge at multiple temperatures in a standard CMOS process. In a second aspect of the invention, a method comprises the step of incorporating the deposition of poly-Ge growth in a standard CMOS process.
1. A method for incorporating one or more germanium layers in a standard CMOS flow, comprising:
providing a silicon-based substrate using a standard CMOS process;
depositing a first silicon oxynitride (Si x O y N z , herein after referred to SON) layer overlying the silicon-based substrate that serves as a mask;
etching the first SON layer onto the silicon-based substrate to form a trench in the SON, thereby forming a SON patterned substrate as defined by a first region of the SON spaced apart laterally from a second region of the SON and above the silicon-based substrate; and
depositing a first germanium layer into a portion of the trench that is incorporated as part of a CMOS process, the trench being formed by the first region of SON, the silicon-based substrate, and the second region of SON.
2. The method of claim 1 , wherein the deposition of the first germanium layer is conducted at a low temperature.
3. The method of claim 2 , wherein the first germanium layer is deposited at the low temperature comprises a thin germanium layer.
4. The method of claim 3 , further comprising depositing a second germanium layer into the trench over the first germanium layer at the low temperature.
5. The method of claim 4 , wherein the second germanium layer comprises a thick germanium layer overlaying the first thin germanium layer at the low temperature.
6. The method of claim 4 , wherein the second germanium layer serves as an active layer or a dummy layer.
7. The method of claim 4 , wherein the deposition of the second germanium layer is conducted at a high temperature.
8. The method of claim 4 , wherein the deposition of the second thick germanium layer is conducted at a high temperature.
9. The method of claim 7 , further comprising implanting the second Ge layer with dopant ions.
10. The method of claim 9 , further comprising quenching one or more defects in the first germanium layer, the second germanium layer, or the first and second germanium layers.
11. The method of claim 10 , further comprising depositing a second SON layer overlaying the second germanium layer for germanium surface passivation.
12. The method of claim 11 , further comprising depositing a dielectric stack overlaying the second SON layer.
13. The method of claim 7 , further comprising depositing a dielectric stack overlaying the second SON layer.
14. The method of claim 10 , further comprising reducing a surface roughness of the second germanium layer by means of an epi-smoothing process.
15. The method of claim 14 , further comprising depositing a second SON layer overlaying the second germanium layer for germanium surface passivation.
16. The method of claim 15 , further comprising depositing a dielectric stack overlaying the second SON layer.
17. The method of claim 7 , further comprising quenching one or more defects in the first germanium layer, the second germanium layer, or the first and second germanium layers.
18. The method of claim 17 , further comprising depositing a second SON layer overlaying the second germanium layer for germanium surface passivation.
19. The method of claim 18 , further comprising depositing a dielectric stack overlaying the second SON layer.
20. The method of claim 17 , further comprising reducing a surface roughness on the second germanium layer by means of an epi-smoothing process.
21. The method of claim 20 , further comprising a second SON layer overlaying the second germanium layer used for germanium surface passivation.
22. The method of claim 21 , further comprising depositing a dielectric stack overlaying the second SON layer.
23. The method of claim 7 , further comprising reducing a surface roughness on the second germanium layer by means of an epi-smoothing process.
24. The method of claim 23 , further comprising a second SON layer overlaying the second germanium layer that is also used for germanium surface passivation.
25. The method of claim 24 , further comprising depositing a dielectric stack overlaying the second SON layer.
26. The method of claim 23 , further comprising quenching one or more defects in the first germanium layer, the second germanium layer, or the first and second germanium layers.
27. The method of claim 26 , further comprising a second SON layer overlaying the second germanium layer that is also used for germanium surface passivation.
28. The method of claim 7 , wherein a second SON layer overlaying the second germanium layer is also used for germanium surface passivation.
29. The method of claim 28 , further comprising depositing a dielectric stack overlaying the second SON layer.
30. The method of claim 4 , further comprising depositing Antimony (Sb) during the growth of the second germanium active layer.
31. The method of claim 30 , further comprising implanting the second Ge layer with dopant ions.
32. The method of claim 31 , further comprising quenching one or more defects in the first germanium layer, the second germanium layer, or the first and second germanium layers.
33. The method of claim 32 , further comprising depositing a second SON layer overlaying the second germanium layer for germanium surface passivation.
34. The method of claim 33 , further comprising depositing a dielectric stack overlaying the second SON layer.
35. The method of claim 7 , further comprising depositing a dielectric stack overlaying the second SON layer.
36. The method of claim 32 , further comprising reducing a surface roughness on the second germanium layer by means of an epi-smoothing process.
37. The method of claim 36 , further comprising depositing a second SON layer overlaying the second germanium layer for germanium surface passivation.
38. The method of claim 37 , further comprising depositing a dielectric stack overlaying the second SON layer.
39. The method of claim 30 , further comprising quenching one or more defects in the first germanium layer, the second germanium layer, or the first and second germanium layers.
40. The method of claim 39 , further comprising depositing a second SON layer overlaying the second germanium layer for germanium surface passivation.
41. The method of claim 40 , further comprising depositing a dielectric stack overlaying the second SON layer.
42. The method of claim 39 , further comprising reducing a surface roughness of the second germanium layer by means of an epi-smoothing process.
43. The method of claim 42 , further comprising a second SON layer overlaying the second germanium layer used for germanium surface passivation.
44. The method of claim 43 , further comprising depositing a dielectric stack overlaying the second SON layer.
45. The method of claim 30 , further comprising reducing a surface roughness on the second germanium layer by means of an epi-smoothing process.
46. The method of claim 45 , further comprising a second SON layer overlaying the second germanium layer that is also used for germanium surface passivation.
47. The method of claim 46 , further comprising depositing a dielectric stack overlaying the second SON layer.
48. The method of claim 45 , further comprising quenching one or more defects in the first germanium layer, the second germanium layer, or the first and second germanium layers.
49. The method of claim 48 , further comprising a second SON layer overlaying the second germanium layer that is also used for germanium surface passivation.
50. The method of claim 30 , wherein the second SON layer overlaying the second germanium layer is also used for germanium surface passivation.
51. The method of claim 50 , further comprising depositing a dielectric stack overlaying the second SON layer.
52. The method of claim 5 , further comprising implanting the second Ge layer with dopant ions.
53. The method of claim 52 , further comprising quenching one or more defects in the first germanium layer, the second germanium layer, or the first and second germanium layers.
54. The method of claim 53 , further comprising depositing a second SON layer overlaying the second germanium layer for germanium surface passivation.
55. The method of claim 54 , further comprising depositing a dielectric stack overlaying the second SON layer.
56. The method of claim 5 , further comprising depositing a dielectric stack overlaying the second SON layer.
57. The method of claim 53 , further comprising reducing a surface roughness on the second germanium layer by means of an epi-smoothing process.
58. The method of claim 57 , further comprising depositing a second SON layer overlaying the second germanium layer for germanium surface passivation.
59. The method of claim 58 , further comprising depositing a dielectric stack overlaying the second SON layer.
60. The method of claim 5 , further comprising quenching one or more defects in the first germanium layer, the second germanium layer, or the first and second germanium layers.
61. The method of claim 60 , further comprising depositing a second SON layer overlaying the second germanium layer for germanium surface passivation.
62. The method of claim 61 , further comprising depositing a dielectric stack overlaying the second SON layer.
63. The method of claim 60 , further comprising reducing a surface roughness on the second germanium layer by means of an epi-smoothing process.
64. The method of claim 63 , further comprising a second SON layer overlaying the second germanium layer used for germanium surface passivation.
65. The method of claim 64 , further comprising depositing a dielectric stack overlaying the second SON layer.
66. The method of claim 5 , further comprising reducing a surface roughness on the second germanium layer by means of an epi-smoothing process.
67. The method of claim 66 , further comprising a second SON layer overlaying the second germanium layer that is also used for germanium surface passivation.
68. The method of claim 67 , further comprising depositing a dielectric stack overlaying the second SON layer.
69. The method of claim 66 , further comprising quenching one or more defects in the first germanium layer, the second germanium layer, or the first and second germanium layers.
70. The method of claim 69 , further comprising a second SON layer overlaying the second germanium layer that is also used for germanium surface passivation.
71. The method of claim 5 , wherein the second SON layer overlaying the second germanium layer is also used for germanium surface passivation.
72. The method of claim 71 , further comprising depositing a dielectric stack overlaying the second SON layer.
73. The method of claim 1 , further comprising performing an epi-clean procedure on the SON patterned substrate.
74. The method of claim 73 , wherein the deposition of the first germanium layer is conducted at a low temperature.
75. The method of claim 74 , wherein the first germanium layer at the low temperature comprises a thin germanium layer.
76. The method of claim 75 , further comprising depositing a second germanium layer into the trench over the first germanium layer at the low temperature.
77. The method of claim 76 , wherein the second germanium layer comprises a thick germanium layer overlaying the first thin germanium layer at the low temperature.
78. The method of claim 76 , wherein the second germanium layer serves as an active layer or a dummy layer.
79. The method of claim 76 , wherein the deposition of the second germanium layer is conducted at a high temperature.
80. The method of claim 76 , wherein the deposition of the second thick germanium layer is conducted at a high temperature.
81. The method of claim 79 , further comprising implanting the second germanium layer with dopant ions.
82. The method of claim 81 , further comprising quenching one or more defects in the first germanium layer, the second germanium layer, or the first and second germanium layers.
83. The method of claim 82 , further comprising depositing a second SON layer overlaying the second germanium layer for germanium surface passivation.
84. The method of claim 83 , further comprising depositing a dielectric stack overlaying the second SON layer.
85. The method of claim 79 , further comprising depositing a dielectric stack overlaying the second SON layer.
86. The method of claim 85 , further comprising reducing a surface roughness on the second germanium layer by means of an epi-smoothing process.
87. The method of claim 82 , further comprising depositing a second SON layer overlaying the second germanium layer for germanium surface passivation.
88. The method of claim 87 , further comprising depositing a dielectric stack overlaying the second SON layer.
89. The method of claim 79 , further comprising quenching one or more defects in the first germanium layer, the second germanium layer, or the first and second germanium layers.
90. The method of claim 89 , further comprising depositing a second SON layer overlaying the second germanium layer for germanium surface passivation.
91. The method of claim 90 , further comprising depositing a dielectric stack overlaying the second SON layer.
92. The method of claim 89 , further comprising reducing a surface roughness on the second germanium layer by means of an epi-smoothing process.
93. The method of claim 92 , further comprising a second SON layer overlaying the second germanium layer used for germanium surface passivation.
94. The method of claim 21 , further comprising depositing a dielectric stack overlaying the second SON layer.
95. The method of claim 79 , further comprising reducing a surface roughness on the second germanium layer by means of an epi-smoothing process.
96. The method of claim 95 , further comprising a second SON layer overlaying the second germanium layer that is also used for germanium surface passivation.
97. The method of claim 96 , further comprising depositing a dielectric stack overlaying the second SON layer.
98. The method of claim 95 , further comprising quenching one or more defects in the first germanium layer, the second germanium layer, or the first and second germanium layers.
99. The method of claim 98 , further comprising a second SON layer overlaying the second germanium layer that is also used for germanium surface passivation.
100. The method of claim 79 , wherein the second SON layer overlaying the second germanium layer is also used for germanium surface passivation.
101. The method of claim 100 , further comprising depositing a dielectric stack overlaying the second SON layer.
102. The method of claim 76 , further comprising depositing Antimony during the growth of the second germanium active layer.
103. The method of claim 102 , further comprising implanting the second germanium layer with dopant ions.
104. The method of claim 103 , further comprising quenching one or more defects in the first germanium layer, the second germanium layer, or the first and second germanium layers.
105. The method of claim 104 , further comprising depositing a second SON layer overlaying the second germanium layer for germanium surface passivation.
106. The method of claim 105 , further comprising depositing a dielectric stack overlaying the second SON layer.
107. The method of claim 102 , further comprising depositing a dielectric stack overlaying the second SON layer.
108. The method of claim 104 , further comprising reducing a surface roughness on the second germanium layer by means of an epi-smoothing process.
109. The method of claim 108 , further comprising depositing a second SON layer overlaying the second germanium layer for germanium surface passivation.
110. The method of claim 109 , further comprising depositing a dielectric stack overlaying the second SON layer.
111. The method of claim 102 , further comprising quenching one or more defects in the first germanium layer, the second germanium layer, or the first and second germanium layers.
112. The method of claim 111 , further comprising depositing a second SON layer overlaying the second germanium layer for germanium surface passivation.
113. The method of claim 112 , further comprising depositing a dielectric stack overlaying the second SON layer.
114. The method of claim 112 , further comprising reducing a surface roughness on the second germanium layer by means of an epi-smoothing process.
115. The method of claim 114 , further comprising a second SON layer overlaying the second germanium layer used for germanium surface passivation.
116. The method of claim 115 , further comprising depositing a dielectric stack overlaying the second SON layer.
117. The method of claim 102 , further comprising reducing a surface roughness on the second germanium layer by means of an epi-smoothing process.
118. The method of claim 117 , further comprising a second SON layer overlaying the second germanium layer that is also used for germanium surface passivation.
119. The method of claim 118 , further comprising depositing a dielectric stack overlaying the second SON layer.
120. The method of claim 117 , further comprising quenching one or more defects in the first germanium layer, the second germanium layer, or the first and second germanium layers.
121. The method of claim 120 , further comprising a second SON layer overlaying the second germanium layer that is also used for germanium surface passivation.
122. The method of claim 102 , wherein the second SON layer overlaying the second germanium layer is also used for germanium surface passivation.
123. The method of claim 122 , further comprising depositing a dielectric stack overlaying the second SON layer.
124. The method of claim 77 , further comprising implanting the second Ge layer with dopant ions.
125. The method of claim 124 , further comprising quenching one or more defects in the first germanium layer, the second germanium layer, or the first and second germanium layers.
126. The method of claim 125 , further comprising depositing a second SON layer overlaying the second germanium layer for germanium surface passivation.
127. The method of claim 126 , further comprising depositing a dielectric stack overlaying the second SON layer.
128. The method of claim 77 , further comprising depositing a dielectric stack overlaying the second SON layer.
129. The method of claim 125 , further comprising reducing a surface roughness on the second germanium layer by means of an epi-smoothing process.
130. The method of claim 129 , further comprising depositing a second SON layer overlaying the second germanium layer for germanium surface passivation.
131. The method of claim 130 , further comprising depositing a dielectric stack overlaying the second SON layer.
132. The method of claim 77 , further comprising quenching one or more defects in the first germanium layer, the second germanium layer, or the first and second germanium layers.
133. The method of claim 132 , further comprising depositing a second SON layer overlaying the second germanium layer for germanium surface passivation.
134. The method of claim 133 , further comprising depositing a dielectric stack overlaying the second SON layer.
135. The method of claim 132 , further comprising reducing a surface roughness on the second germanium layer by means of an epi-smoothing process.
136. The method of claim 135 , further comprising a second SON layer overlaying the second germanium layer used for germanium surface passivation.
137. The method of claim 136 , further comprising depositing a dielectric stack overlaying the second SON layer.
138. The method of claim 77 , further comprising reducing a surface roughness on the second germanium layer by means of an epi-smoothing process.
139. The method of claim 138 , further comprising a second SON layer overlaying the second germanium layer that is also used for germanium surface passivation.
140. The method of claim 139 , further comprising depositing a dielectric stack overlaying the second SON layer.
141. The method of claim 138 , further comprising quenching one or more defects in the first germanium layer, the second germanium layer, or the first and second germanium layers.
142. The method of claim 141 , further comprising a second SON layer overlaying the second germanium layer that is also used for germanium surface passivation.
143. The method of claim 77 , wherein the second SON layer overlaying the second germanium layer is also used for germanium surface passivation.
144. The method of claim 143 , further comprising depositing a dielectric stack overlaying the second SON layer.
145. The method of claim 1 , further comprising depositing a seed layer into a portion of the trench formed by the first region of the SON, the silicon-based substrate, and the second region of the SON.
146. The method of claim 145 , wherein the seed layer comprises a silicon layer.
147. The method of claim 145 , wherein the seed layer comprises an amorphous layer.
148. The method of claim 145 , wherein the seed layer comprises a poly-crystalline layer.
149. The method of claim 145 , wherein the seed layer comprises a germanium amorphous layer.
150. The method of claim 145 , wherein the seed layer comprises a germanium poly-crystalline layer.
151. The method of claim 145 , wherein the deposition of the seed layer is conducted at a low temperature.
152. The method of claim 151 , further comprising performing a lithography on the first germanium layer and the silicon amorphous layer thereby creating a germanium pad. (let's discuss).
153. The method of claim 152 , further comprising depositing a second germanium layer into the trench over the first germanium layer.
154. The method of claim 151 , further comprising depositing a second germanium layer into the trench over the first germanium layer.
155. The method of claim 154 , further comprising performing a lithography on the first and second germanium layers thereby creating a germanium pad.
156. The method of claim 154 , further comprising implanting the second germanium layer with dopant ions.
157. The method of claim 156 , further comprising annealing the germanium file by modulating a film temperature between a low temperature and a high temperature for a plurality of cycles, the size and orientation of the germanium film allowing a lower low temperature in the low temperature than a typical low temperature and a lower high temperature in the high temperature than a typical high temperature.
158. The method of claim 157 , further comprising reducing a surface roughness on the second germanium layer by means of an epi-smoothing process.
159. The method of claim 154 , further comprising depositing Antimony during the growth of the second germanium active layer.
160. The method of claim 159 , further comprising reducing a surface roughness on the second germanium layer by means of an epi-smoothing process.
161. The method of claim 159 , further comprising annealing the germanium film by modulating film temperature between a low temperature and a high temperature for a plurality of cycles, the size and orientation of the germanium film allowing a lower low temperature in the low temperature than a typical low temperature and a lower high temperature in the high temperature than a typical high temperature.
162. The method of claim 161 , further comprising reducing a surface roughness by means of an epi-smoothing process.
163. The method of claim 159 , further comprising implanting the second germanium layer with dopant ions.
164. The method of claim 163 , further comprising annealing the germanium file by modulating a film temperature between a low temperature and a high temperature for a plurality of cycles, the size and orientation of the germanium film allowing a lower low temperature in the low temperature than a typical low temperature and a lower high temperature in the high temperature than a typical high temperature.
165. The method of claim 164 , further comprising reducing a surface roughness on the second germanium layer by means of an epi-smoothing process.
166. The method of claim 1 , between the providing step and the depositing step of the first silicon oxynitride, further comprising depositing one or more additional silicon oxynitride layers between the silicon-based substrate and the first silicon oxynitride.
167. The method of claim 166 , wherein the first silicon oxynitride is selected of a different chemical composition from the one or more additional silicon oxynitride layers.
168. The method of claim 166 , wherein the one or more additional silicon oxynitride layers are selected of a different chemical composition between themselves.
169. The method of claim 1 , wherein the parameters of y or z in the Si x O y N z is zero.
170. The method of claim 166 , wherein the parameters of y or z in the Si x O y N z is zero.
171. The method of claim 1 , wherein the silicon-based substrate comprises a silicon-on-insulator (SOI) substrate.
172. The method of claim 1 , wherein the silicon-based substrate comprises a silicon-on-sapphire (SOS) substrate.
173. The method of claim 1 , wherein the silicon-based substrate comprises a silicon germanium layer.