Method of fabricating a semiconductor pn junction
AssigneeJun-Ichi Nishizawa
InventorsJun-ichi Nishizawa, Kazuomi Ito, Yasuo Okuno
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Abstract
A method of forming a pn junction with a Group IIB-VIB compound semiconductor containing Zn is disclosed, the method including preparing an n type semiconductor region either locally or entirely in a Group IIB-VIB compound semiconductor crystal obtained by relying on a crystal growth method in liquid phase using a temperature difference technique, and subjecting this crystal to a thermal annealing in a Zn solution or in a Zn atmosphere to produce an n type region. Crystal growth is conducted while controlling the vapor pressure of the constituent Group IVB element to produce a p type region. A combination of all these steps gives a more stable pn junction.
Claims8
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.
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.
Dependencies are inferred from the claim text.