ESTABLISHING A HIGH PHOSPHORUS CONCENTRATION IN SOLAR CELLS
First Claim
1. A method of creating a high dopant concentration near the surface of a solar cell, comprising;
- utilizing a silicon substrate;
introducing a dopant into said substrate; and
introducing carbon into said substrate, wherein said carbon limits the diffusion of said dopant.
2 Assignments
0 Petitions
Accused Products
Abstract
Methods of controlling the diffusion of a dopant in a solar cell are disclosed. A second species is used in conjunction with the dopant to modify the diffusion region. For example, phosphorus and boron both diffuse by pairing with interstitial silicon atoms. Thus, by controlling the creation and location of these interstitials, the diffusion rate of the dopant can be controlled. In one embodiment, a heavier element, such as germanium, argon or silicon, is used to create interstitials. Because of the presence of these heavier elements, the dopant diffuses deeper into the substrate. In another embodiment, carbon is implanted. Carbon reduces the number of interstitials, and thus can be used to limit the diffusion of the dopant. In another embodiment, a lighter element, such as helium is used to amorphize the substrate. The crystalline-amorphous interface created limits diffusion of the dopant into the substrate.
-
Citations
20 Claims
-
1. A method of creating a high dopant concentration near the surface of a solar cell, comprising;
-
utilizing a silicon substrate; introducing a dopant into said substrate; and introducing carbon into said substrate, wherein said carbon limits the diffusion of said dopant. - View Dependent Claims (2, 6, 7, 8, 9, 10, 11, 12)
-
- 3. The method of claim 3, wherein said dopant and said carbon are introduced via ion implantation, wherein a molecule comprising said dopant and said carbon is ionized.
-
13. A method of modifying a dopant concentration of a solar cell, comprising;
-
utilizing a silicon substrate; introducing a dopant into said substrate; and introducing a second species into said substrate, wherein said second species increases the number of silicon interstitials within said solar cell. - View Dependent Claims (14, 15, 16)
-
-
17. A method of creating a high dopant concentration near the surface of a solar cell, comprising;
-
utilizing a silicon substrate; introducing a dopant into said substrate; and introducing helium into said substrate, wherein said helium limits the diffusion of said dopant. - View Dependent Claims (18, 19, 20)
-
Specification