Gas curtain continuous chemical vapor deposition production of semiconductor bodies

A continuous process for preparing bodies of semiconductor material comprising:

• (a) pulling a virgin slim rod in situ in a pulling chamber from the float zone reaction of a seed crystal and molten semiconductor materials source, the material source being continuously supplied;
• (b) heating the slim rod to decomposition temperature of gaseous compounds containing suitable semiconductor material for deposition upon the slim rod;
• (c) passing the heated slim rod through a communication zone between the pulling chamber and the chemical vapor deposition chamber;
• (d) maintaining the slim rod at a temperature sufficient for decomposing the gaseous compounds through focused radiant heat furnace means while contacting the slim rod countercurrently with the decomposable gaseous compounds;
• (e) creating a gas curtain along the chemical vapor deposition chamber inner wall substantially preventing the gaseous compounds from reaching the wall;
• (f) enlarging the slim rod diameter as a result of thermal decomposition of the gaseous compounds;
• and
• (g) pulling the resulting enlarged semiconductor body from the deposition chamber through gas lock and cooling means.

A continuous process for preparing bodies of single crystal silicon comprising:

• (a) pulling a virgin single crystal silicon slim rod in situ in a pulling chamber from the reaction of a seed crystal and a continuous source of molten silicon;
• (b) heating the virgin slim rod to decomposition temperature of gaseous silicon compounds which will thermally decompose upon the heated slim rod;
• (c) passing the heated slim rod into a chemical vapor deposition chamber;
• (d) maintaining surface temperatures of the rod, from about 1,000.degree. C. to about 1,300.degree. C. through heat focusing means;
• (e) contacting the rod surfaces with a gas having the formula Si.sub.k H.sub.m X.sub.n where k is a number from 1 to 2, m is a number of from 0 to 6, n is a number of from 0 to 6 and X is a halogen;
• (f) creating a gas curtain along the chemical vapor deposition chamber inner wall substantially preventing the gaseous compounds from reaching the wall;
• (g) depositing silicon on the single crystal rod surfaces as the rod is moved through the chemical vapor deposition chamber;
• and
• (h) withdrawing the resulting enlarged single crystal silicon body from the chemical vapor deposition chamber.

A continuous process for preparing bodies of polysilicon comprising:

• (a) pulling one or more virgin silicon slim rods in situ in a pulling chamber from the reaction of one or more seed crystals and a continuous source of molten silicon;
• (b) preheating and introducing the silicon slim rods into a chemical vapor deposition chamber;
• (c) simultaneously heating and contacting the introduced slim rods to decomposition temperature of silicon containing gaseous compounds;
• (d) maintaining slim rods at a temperature sufficient for decomposing silicon containing gaseous compounds while passing slim rods through the chemical vapor deposition chamber;
• (e) creating a gas curtain along the chemical vapor deposition chamber inner wall substantially preventing the gaseous compounds from reaching the wall;
• (f) enlarging the slim rod's diameter as a result of thermal decomposition of the silicon containing gaseous compounds;
• and
• (g) pulling the resulting enlarged polysilicon bodies from the chemical vapor deposition chamber.

Apparatus for continuous growth of semiconductor material bodies comprising:

• (a) a slim rod growth chamber having an upper end in communication with the vapor deposition chamber lower end through a narrowed passageway of sufficient diameter to allow passage of the slim rod from the growth chamber into the chemical vapor deposition chamber without touching;
• the growth chamber in lower end communication with a continuous source of semiconductor feed rod which provides a melt source through high energy heating coil means;
• (b) a withdrawable pulling means extending downward through the chemical vapor deposition chamber and into the growth chamber;
• (c) growth chamber slim rod heating means;
• (d) geometrically focusing radiant furnace surrounding the chemical vapor deposition chamber walls, the chamber walls being transparent to the focused heat;
• (e) growth chamber entering gas pressure source means;
• (f) reaction gas entering and exit means to the chemical vapor deposition chamber;
• (g) gas entry flow guide means which provide a gas curtain along the chemical vapor deposition chamber inner wall substantially preventing the gaseous compounds from reaching the wall;
• and
• (h) exit means from the chemical vapor deposition chamber upper end comprised of a gas seal means.