Crucible for holding molten semiconductor materials

Claim 2

The invention as defined in claim 1 wherein said crucible body is additionally formed with at least one other hemispherical recess for holding a quantity of source material of a different conductivity type than the source material confined in said first mentioned hemispherical recess; and actuating means operably connected to said first portion of said crucible body for selectively locating a selected one of said hemispherical recesses so that the surface center of the source material held therein will lie substantially along the central vertical axis of the vacuum apparatus.

Claim 3

The invention as defined in claim 3 wherein said actuating means includes a lead screw mechanism operably coupled between said crucible body and the vacuum apparatus and having means located externally of the vacuum apparatus for manually operating said mechanism so as to locate said selected one of said hemispherical recesses to an alternate position without the necessity of breaking the ultrahigh vacuum created in the vacuum apparatus.

Claim 4

The invention as defined in claim 4 wherein said crucible body first portion constitutes a base fixedly supported on the vacuum apparatus and said second portion of said crucible body movably carried on said base and wherein said recirculating means include longitudinal passageways provided in said base for conducting said cooling agent therethrough.

Claim 5

The invention as defined in claim 5 wherein said first portion of said crucible body is slidably mounted on said base by correspondingly mated ribs and grooves formed in respective opposing and adjacent surfaces thereof constituting an interconnection construction defining said thermal compression interlock having high thermal energy transfer characteristics so that said base serves as an efficient heat sink.

Claim 6

A crucible apparatus for holding molten source material within a vacuum environment comprising: a crucible body formed of a material which is electrically and thermally conductive so as to be adapted for operation as an element in an electrical circuit and being further formed with a plurality of hemispherical recesses adapted to hold quantities of source materials of different conductivity types; a fixed base for movably supporting said crucible body so that a selected hemispherical recess can be located in a predetermined position within said vacuum environment; means for recirculating a cooling agent through said base whereby said base and said crucible body cooperate as a heat sink for dissipating heat of the source material; and an interconnection construction movably coupling said crucible body to said base constituting a thermal energy transmission path therebetween whereby maximum heat gradients are transferred from said crucible body to said base eliminating diffusion of material from said crucible body into the source material.

Claim 7

The invention as defined in claim 7 wherein said interconnection construction includes a plurality of elongated grooves and ribs formed in each of the opposing and contacting surfaces of adjacent sides of said crucible body and said base and wherein said plurality of grooves and ribs of the respective surfaces are mated together in frictional contact to provide maximum high pressure surface contact therebetween.

Claim 8

The invention as defined in claim 8 including means coupled to said crucible body for selectively moving said crucible body with respect to said base without the necessity of breaking the vacuum environment.

Claim 9

The invention as defined in claim 9 wherein each of said plurality of recesses are provided with a chromium liner corresponding to the hemispherical contour thereof adapted to separate the source material from said cruCible body and operable as an optical heater whereby radiant heat from the source material melt at the surface center thereof is reflected back to the surface center to augment heating of the source material.

Claim 10

The invention as defined in claim 8 wherein said interconnection construction forms a thermal compression lock between said mated ribs and grooves.

Claim 11

The invention as defined in claim 7 wherein said interconnection construction provides a thermal expansion differential between said crucible body and said base which creates a thermal compression interlock that physically connects said crucible body and said base together and further provides a low series thermal resistance to said cooling agent.