NOVELTY - A solar cell comprises a semiconductor body (10) having first and second opposing surfaces; a first dielectric layer (12) on the first surface; a second dielectric layer (16) containing a tunnel oxide, on the second surface; a first pattern of acceptor doped semiconductor material (18) over the tunnel oxide; a second pattern of donor doped semiconductor material (22) over the tunnel oxide and interleaved with the first pattern; and a first conductive pattern (24) interconnecting the acceptor doped material and a second conductive pattern (26) interconnecting the donor doped material.    USE - As a solar cell such as interdigitated back contact solar cell for direct conversion of solar radiation into electrical energy, useful in microelectronics.    ADVANTAGE - The use of acceptor and donor amorphous silicon contacts on the structure obviates the need for photoresist masking and dopant diffusion and the high temperature processing required in annealing the diffused dopants. The tunnel silicon oxide placed between the contacts and the substrate, prevents epitaxial growth of the amorphous silicon on the substrate. The back contact heterojunction enhances the rear passivation of the solar cell by the inclusion of tunnel oxide, heterojunction field provided by the amorphous silicon contacts, and contact passivation. The process of making the device does not require high temperature dopant drive. The heterojunction solar cell using doped amorphous silicon contacts is readily fabricated using conventional semiconductor processing techniques without the for high temperature processing. The solar cell is efficient in operation and economical to manufacture.    DETAILED DESCRIPTION - A solar cell comprises a semiconductor body (10) having first and second opposing major surfaces; a first dielectric layer (12) on the first surface; a second dielectric layer (16) containing a tunnel oxide, on the second surface; a first pattern of acceptor doped semiconductor material (18) over the tunnel oxide on the second surface; a second pattern of donor doped semiconductor material (22) over the tunnel oxide on the second surface and interleaved with the first pattern; and a first conductive pattern (24) interconnecting the acceptor doped semiconductor material and a second conductive pattern (26) interconnecting the donor doped semiconductor material. An INDEPENDENT CLAIM is included for fabricating a silicon solar cell, involving fabricating carrier acceptor contacts by providing a silicon substrate having first and second opposing major surfaces, forming a tunnel silicon oxide layer on the first major surface, and forming a doped amorphous silicon layer on the tunnel silicon oxide.    DESCRIPTION OF DRAWING(S) - The figure shows a sectional side view of an interdigitated back contact solar cell including doped amorphous contact.    first dielectric layer (12)    second dielectric layer (16)    first pattern of acceptor doped semiconductor material (18)    second pattern of donor doped semiconductor material (22)    first conductive pattern (24)    second conductive pattern. (26)