Induction heated reactor system for chemical vapor deposition

Claim 2

In a chemical vapor deposition system, in combination: a generally closed reaction chamber having walls formed from a dielectric material? a susceptor for carrying a plurality of semiconductor wafers, said susceptor being adapted to be positioned within said chamber and being formed from an electrically conductive material adapted to be heated by induction; an induction coil positioned in the vicinity of said susceptor for carrying an alternating electric current to produce induction heating of said susceptor and thereby heating said wafers thereon; means supplying said induction coil with alternating electric current at a prearranged frequency to induce heating currents throughout a region of said susceptor having a skin depth directly related to said prearranged frequency; said susceptor being formed to have a general thickness less than or equal to said skin depth, and having regions of substantially reduced thickness at prearranged locations relative to wafer positions on said susceptor to produce greater induced heating at said prearranged locations and thereby to alter the temperature of said susceptor at said regions.

Claim 3

The system of Claim 1, wherein said susceptor has predefined wafer positions thereon, and said regions of substantially reduced thickness of said susceptor are positioned at locations which produce a substantially uniform temperature profile across said susceptor at said predefined wafer positions.

Claim 4

The system of claim 1 or claim 2,further comprising reflector means facing said susceptor and wafers carried thereon for reflecting heat energy radiated from said susceptor and said wafers back to said susceptor and said wafers to reduce substantially the heat loss therefrom and thereby to reduce substantially the thermal gradient from front to back surfaces of said wafers; the combination of said uniform temperature profile of said susceptor at said predefined wafer positions and said reduced thermal gradient in said wafers providing substantially slip-free heating conditions for said wafers and substantially uniform deposition rates on said wafers during a deposition process carried out in said system.

Claim 6

The system of Claim 4, wherein said susceptor body comprises a central wafer carrying wall region and upper and lower wall regions of substantial length which dispose the upper and lower extremities of said central wafer carrying wall region a substantial distance from the top and bottom ends of said susceptor, said upper and lower wall regions having a wall thickness substantially less than said central wall region to produce substantially greater induction heating of said upper and lower wall regions and thereby to provide a more uniform temperature profile from top to bottom of said susceptor.

Claim 7

In a chemical vapor deposition system, in combination: a generally cylindrical reaction chamber having walls formed from a dielectric material and being disposed with its central axis in a vertical orientation; a susceptor formed from an electrically conductive material adapted to be heated by induction, said susceptor comprising a hollow body having a generally truncated pyramidal configuration and adapted to be positioned within said reaction chamber with its central axis disposed in a vertical orientation, said body having an arrangement of substantially straight side wall segments meeting at corner regions and including an array of wafer carrying recesses formed on front surface regions thereof in multiple rows such that said wafers face the cylindrical side walls of said reaction chamber? a heating system for heating said susceptor by induction and comprising a coil having a generally cylindrical configuration disposed over said second chamber and having a height greater than the height of said susceptor, and power supply means for supplying an alternating current to said coil for induction heating of said susceptor; gas delivery means for delivering reactant gases to said reaction chamber in a region above said susceptor and for withdrawing reactant gases from said reaction chamber below said susceptor; and boundary control means carried on said susceptor at prearranged locations relative to said wafer carrying recesses to locally alter the boundary conditions between said reactant gases and the surfaces of said susceptor and wafers carried thereon and thereby to provide more uniform deposition of material on said wafers.

Claim 8

In a chemical vapor deposition system, in combination: a generally cylindrical reaction chamber having walls formed from a dielectric material and being disposed with its central axis in a vertical orientation; a susceptor formed from an electrically conductive material adapted to be heated by induction, said susceptor comprising a hollow body having a generally truncated pyramidal configuration and adapted to be positioned within said reaction chamber with its central axis disposed in a vertical orientation, said body having an arrangement of substantially straight side wall segments meeting at corner regions and including an array of wafer carrying recesses formed on front surface regions thereof in multiple rows such that said wafers face the cylindrical side walls of said reaction chamber? a heating system for heating said susceptor by induction and comprising a coil having a generally cylindrical configuration disposed over said second chamber and having a height greater than the height of said susceptor, and power supply means for supplying an alternating current to said coil for induction heating of said susceptor; gas delivery means for delivering reactant gases to said reaction chamber in a region above said susceptor and for withdrawing reactant gases from said reaction chamber below said susceptor; and boundary control means carried on said susceptor at prearranged locations relative to said wafer carrying recesses to locally alter the boundary conditions between said reactant gases and the surfaces of said susceptor and wafers carried thereon and thereby to provide more uniform deposition of material on said wafers.

Claim 9

The system of Claim 6, wherein said boundary control means include means defining a wall surface region projecting radially outward from said susceptor at a position spaced above a top row of said wafer carrying recesses to equalize the relative deposition of material on wafers in said top row with respect to wafers in lower rows of wafer carrying recesses on said susceptor.

Claim 10

The system of Claim 7, wherein said means defining said projecting wall surface region comprises a top cap carried on the top edge of said susceptor and having marginal edge regions overhanging the adjacent front wall surfaces of said susceptor.

Claim 12

The system of Claim 9, wherein said means defining contoured wall surface regions comprises contoured outwardly projecting edge regions integrally formed on said susceptor at said regions.