Formation of multilayer dopant distributions in a semiconductor
AssigneeBell Telephone Laboratories, Incorporated
InventorsHarry J. Leamy, Thomas E. Seidel
Life of this patent
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Abstract
A method of making solid state devices having multilayer dopant distributions, including p-p+ and n-n+ junctions, etc. A semiconductor body is rapidly melted, typically by a laser, electron beam, or ion beam. Present in the melt is a first dopant having a low segregation coefficient and a second dopant having a high segregation coefficient. During rapid resolidification of the melt, the first dopant segregates toward the surface, while the second dopant remains substantially in place, producing a junction. The production of diodes, bipolar and field effect transistors, Schottky barriers, ohmic contacts, junction isolated surface regions, high conductivity paths, etc., is possible by this method.
Claims18
A method of making a semiconductor device by steps comprising melting one or more times a surface region of a semiconductor body by means of a radiation beam, wherein the duration of each melting at a given location on said body is less than 10 milliseconds, and wherein said melting extends into a single crystal region of said semiconductor body, with said single crystal region having a given dopant type immediately beneath said melted region,
- CHARACTERIZED IN THAT
- the melted region comprises a first dopant having an equilibrium segregation coefficient of less than 0.1, and a second dopant having an equilibrium segregation coefficient of greater than 0.1, with at least said second dopand being deposited on, or introduced in, said surface region prior to said melting, and with said melting extending to a depth greater than the depth of such deposited or introduced dopant or dopants prior to said melting, whereby a junction is formed within said region upon resolidification of the melt.
Dependencies are inferred from the claim text.