Sumco Corporation

Sumitomo Mitsubishi Silicon Corporation

Takayuki Dohi

Masayuki Ishibashi

Masato Sakai

Takashi Fujikawa

Shinji Nakahara

John F Krueger

Daizo Horie

Masaya Sakurai

A method for growing an epitaxial film on a surface of a semiconductor wafer by mounting the wafer within a susceptor pocket and supplying source gas and carrier gas to the upper surface side of the susceptor and supplying carrier gas to the lower surface side of the susceptor. The susceptor includes a substantially circular bottom wall and a sidewall encompassing the bottom wall to form a pocket for mounting the wafer, wherein a plurality of circular through-holes are formed in the bottom wall in an outer peripheral region a distance of up to about &#xbd; the radius toward the center of the bottom wall. The total opening surface area of the through-holes is 0.05 to 55% of the surface area of the bottom wall, the opening surface area of each through-hole is 0.2 to 3.2 mmand the density of the through-holes is 0.25 to 25 per cm.

Epitaxial growth method

A method of producing an epitaxial wafer, comprising: performing epitaxial growth of silicon on a main surface of a wafer made of a silicon single crystal; performing surface flattening pretreatment of a main surface of the wafer using a treatment liquid of a predetermined composition at a temperature of 100&#xb0; C. or less, thereby forming an oxide film of a predetermined thickness while removing particles adhered on the main surface of the wafer; and performing a surface polishing step where the main surface of the wafer is mirror polished.

Epitaxial wafer and method of producing same

A susceptor for use in an epitaxial growth apparatus and method where a plurality of circular through-holes are formed in the bottom wall of a pocket in an outer peripheral region a distance of up to about &#xbd; the radius toward the center of the circular bottom wall. The total opening surface area of these through-holes is 0.05 to 55% of the surface area of the bottom wall. The opening surface area of each of the through-holes provided at this outer peripheral region is 0.2 to 3.2 mmand the density of the through-holes is 0.25 to 25 per cm. After a semiconductor wafer is mounted in the pocket, epitaxial growth is carried out while source gas and carrier gas (i.e., reactive gas) is made to flow on the upper surface side of the susceptor and carrier gas is made to flow on the lower surface side.

Epitaxial growth susceptor

An epitaxial silicon wafer is provided in which an epitaxial layer is grown on a silicon wafer having a plane inclined from a {110} plane of a silicon single crystal as a main surface. In the silicon wafer for growing the epitaxial layer thereon, an inclination angle azimuth of the {110} plane is in the range of 0 to 45 degrees as measured from a &#x3c;100&#x3e; orientation parallel to the {110} plane toward a &#x3c;100&#x3e; direction. With such an arrangement, LPDs of 100 nm or less can be measured from a {110} wafer that has a carrier mobility (including the hole and electron mobilities) higher than that of a {100} wafer. Also, surface roughness degradation in the {110} wafer can be suppressed. Also, the surface state of the {110} wafer can be measured. Further, a quality evaluation can be performed on the {110} wafer.

Epitaxial silicon wafer and fabrication method thereof

An epitaxial silicon wafer is provided in which an epitaxial layer is grown on a silicon wafer having a plane inclined from a {110} plane of a silicon single crystal as a main surface. In the silicon wafer for growing the epitaxial layer thereon, an inclination angle azimuth of the {110} plane is in the range of 0 to 45 degrees as measured from a &#x3c;100&#x3e; orientation parallel to the {110} plane toward a &#x3c;110 &#x3e; direction. With such an arrangement, LPDs of 100 nm or less can be measured from a {110} wafer that has a carrier mobility (including the hole and electron mobilities) higher than that of a {100 } wafer. Also, surface roughness degradation in the {110} wafer can be suppressed. Also, the surface state of the {110} wafer can be measured. Further, a quality evaluation can be performed on the {110} wafer.

A single opening is formed in a central portion of a susceptor of a vapor phase epitaxial growth system. Consequently, any dopant diffused off outwardly from the back surface of a wafer during an epitaxial growth process can be exhausted through the opening to the beneath side with respect to the susceptor. As a result, it may become difficult for auto-doping to be induced, even with no protective film formed on a back surface of the wafer. Uniformity in a dopant concentration in the surface may be improved and thus a resistivity may be made uniform. Further, since a temperature of the back surface of the wafer is measured through the opening, a heating temperature can be controlled stably, thus allowing a precise temperature control thereof. Consequently, the epitaxial film as well as the distribution of its resistivity may be made uniform across the entire wafer.

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Tokyo, Japan

Takayuki Dohi