Method of fabricating a semiconductor pn junction

Claim 1

A method of forming a pn junction with a Group IIB-VIB compound semiconductor crystal containing Zn as a crystal-constituent Group IIB element, substantially to the exclusion of Te as a constituent element of said compound semiconductor crystal, said method comprising the steps of: (a) using as a solvent a mixture of Te and a crystal-constituent Group VIB element other than Te; (b) charging a Group IB element as a p type impurity into said solvent; (c) floating a source crystal of sid group IIB-VIB compound semiconductor on the surface of said solvent; (d) establishing a temperature difference between said source crystal and a surface of a crystal deposition zone; (e) depositing a p type crystal at said crystal deposition zone at a constant temperature; (f) making a wafer by slicing the crystal thus obtained; and (g) heat treating the resulting wafer in a Zn atmosphere, thereby forming an n type layer locally in said p type crystal to provide a pn junction in said wafer.

Claim 2

A method of forming a pn junction with a Group IIB-VIB compound semiconductor crystal containing Zn as a crystal-constituent Group IIB element, substantially to the exclusion of Te as a constituent element of said compound semiconductor crystal, said method comprising the steps of: (a) using as a solvent a mixture of Te and a crystal-constituent Group VIB element other than Te; (b) charging a Group IB element as a p type impurity into said solvent; (c) floating a source crystal of sid group IIB-VIB compound semiconductor on the surface of said solvent; (d) establishing a temperature difference between said source crystal and a surface of a crystal deposition zone; (e) depositing a p type crystal at said crystal deposition zone at a constant temperature; (f) making a wafer by slicing the crystal thus obtained; and (g) heat treating the resulting wafer in a Zn atmosphere, thereby forming an n type layer locally in said p type crystal to provide a pn junction in said wafer.

Claim 7

A method of forming a pn junction with a Group IIB-VIB compound semiconductor crystal containing Zn as a crystal-constituent Group IIB element, substantially to the exclusion of Te as a constituent element of said compound semiconductor crystal, said method comprising the steps of: (a') using as a solvent a mixture of Te and a crystal constituent Group VIB element other than Te; (b') floating a source crystal of said Group IIB-VIB compound semiconductor on the surface of said solvent; (c') establishing a temperature difference between said source crystal and a crystal deposition zone; (d') causing the deposition of a crystal having high resistivity in said deposition zone at constant temperature; (e') making a wafer by slicing the crystal and subjecting said wafer to a heat treatment in a Zn solution to render the whole wafer to a low resistive n type; and (f') diffusing, into the resulting wafer, a p type impurity while controlling, at a predetermined value, a vapor pressure of the VIB element which is a constituent element of said Group IIB-VIB semiconductor, thereby forming a pn junction in said n type crystal.

Claim 8

A method of forming a pn junction with a Group IIB-VIB compound semiconductor crystal containing Zn as a crystal-constituent Group IIB element, substantially to the exclusion of Te as a constituent element of said compound semiconductor crystal, said method comprising the steps of: (a') using as a solvent a mixture of Te and a crystal constituent Group VIB element other than Te; (b') floating a source crystal of said Group IIB-VIB compound semiconductor on the surface of said solvent; (c') establishing a temperature difference between said source crystal and a crystal deposition zone; (d') causing the deposition of a crystal having high resistivity in said deposition zone at constant temperature; (e') making a wafer by slicing the crystal and subjecting said wafer to a heat treatment in a Zn solution to render the whole wafer to a low resistive n type; and (f') diffusing, into the resulting wafer, a p type impurity while controlling, at a predetermined value, a vapor pressure of the VIB element which is a constituent element of said Group IIB-VIB semiconductor, thereby forming a pn junction in said n type crystal.