Globalwafers Co., Ltd.

Memc Electronic Materials, Inc.

Zheng Lu

Feng-Chien Tsai

Gaurab Samanta

Tse-Wei Lu

Steven Lawrence Kimbel

Hong-Huei Huang

Ying Tao

Sumeet S Bhagavat

Mohsen Banan

Lee William Ferry

Carl F Cherko

Chun-Chin Tu

Shan-Hui Lin

Joseph C Holzer

Chun-Sheng Wu

Robert H Fuerhoff

Hsien-Ta Tseng

Wei-Chen Chou

Vahid Khalajzadeh

Tapas Jain

Chi-Yung Chen

Ingot puller apparatus that include a silicon feed tube for adding solid silicon to a crucible assembly are disclosed. The silicon feed tubes include a conduit portion having an inner diameter and a kick plate disposed below the conduit portion. The kick plate extends across at least 60% of the inner diameter of the conduit portion.

Ingot puller apparatus having silicon feed tubes with kick plates

Nitrogen-doped CZ silicon crystal ingots and wafers sliced therefrom are disclosed that provide for post epitaxial thermally treated wafers having oxygen precipitate density and size that are substantially uniformly distributed radially and exhibit the lack of a significant edge effect. Methods for producing such CZ silicon crystal ingots are also provided by controlling the pull rate from molten silicon, the temperature gradient and the nitrogen concentration. Methods for simulating the radial bulk micro defect size distribution, radial bulk micro defect density distribution and oxygen precipitation density distribution of post epitaxial thermally treated wafers sliced from nitrogen-doped CZ silicon crystals are also provided.

Nitrogen doped and vacancy dominated silicon ingot and thermally treated wafer formed therefrom having radially uniformly distributed oxygen precipitation density and size

Methods for determining suitability of Czochralski growth conditions to produce silicon substrates for epitaxy. The methods involve evaluating substrates sliced from ingots grown under different growth conditions (e.g., impurity profiles) by imaging the wafer by infrared depolarization. An infrared depolarization parameter is generated for each epitaxial wafer. The parameters may be compared to determine which growth conditions are well-suited to produce substrates for epitaxial and/or post-epi heat treatments.

Methods for determining suitability of Czochralski growth conditions for producing substrates for epitaxy

Methods for determining suitability of a silicon substrate for epitaxy and/or for determining slip resistance during epitaxy and post-epitaxy thermal treatment are disclosed. The methods involve evaluating different substrates of the epitaxial wafers by imaging the wafer by infrared depolarization. An infrared depolarization parameter is generated for each epitaxial wafer. The parameters may be compared to determine which substrates are well-suited for epitaxial and/or post-epi heat treatments.

Methods for determining suitability of silicon substrates for epitaxy

A system for producing a silicon ingot, the system includes a crystal puller, a pyrometer, an infrared (IR) camera, and a controller. The crystal puller includes a hot zone having one or more components therein, and in which a silicon ingot may be pulled. The pyrometer is positioned to view a region of interest within the hot zone. The IR camera is positioned to view one or more additional regions of interest within the hot zone. The controller is connected to the crystal puller, the pyrometer, and the IR camera. The controller is programmed to control the crystal puller to produce a silicon ingot, receive temperature data of the region of interest within the hot zone from the pyrometer while producing the silicon ingot, and receive IR images of the one or more additional regions of interest from the IR camera while producing the silicon ingot.

Methods and systems of capturing transient thermal responses of regions of crystal pullers

A method for growing a single crystal silicon ingot by the Czochralski method having reduced deviation in diameter is disclosed.

Process for preparing ingot having reduced distortion at late body length

System for controlling crystal growth in a Czochralski crystal growing apparatus. A magnetic field is applied within the crystal growing apparatus and varied to control a shape of the melt-solid interface where the ingot is being pulled from the melt. The shape of the melt-solid interface is formed to a desired shape in response to the varied magnetic field as a function of a length of the ingot.

Controlling melt-solid interface shape of a growing silicon crystal using a variable magnetic field

A method of continuously measuring an elevation and shape of an unmelted polycrystalline silicon island during a silicon meltdown process. The method comprises projecting a focused bright light on the silicon island to produce a bright dot on the silicon island. The method also includes electronically determining an elevation and a shape of the silicon island by tracking the bright dot during the meltdown process.

Method and device for continuously measuring silicon island elevation

Methods and system for controlling crystal growth in a Czochralski crystal growing apparatus. A magnetic field is applied within the crystal growing apparatus and varied to control a shape of the melt-solid interface where the ingot is being pulled from the melt. The shape of the melt-solid interface is formed to a desired shape in response to the varied magnetic field as a function of a length of the ingot.

The present invention is directed to a process for preparing single crystal silicon, in ingot or wafer form, wherein crucible rotation is utilized to control the average axial temperature gradient in the crystal, G, as a function of radius (i.e., G(r)), particularly at or near the central axis. Additionally, crucible rotation modulation is utilized to obtain an axially uniform oxygen content therein.

Process for preparing single crystal silicon using crucible rotation to control temperature gradient

A method and apparatus for controlling the quenching rate of a monocrystalline ingot pulled from a melt by adjusting one or more post growth processing parameter. A temperature model generates a temperature profile that represents the surface temperature along the length of the ingot at the instant it is pulled from the melt. A first temperature at a particular location along the length of the crystal is determined from the temperature profile. A temperature sensor senses a second temperature at the same particular location. A PLC calculates a quenching rate of the crystal as a function of the first temperature and the second temperature. The PLC generates an error between a target quenching rate and a calculated quenching rate, and one or more post growth process parameters are adjusted as function of the error signal to optimize the quenching rate. Alternatively, temperature readings from the sensor are collected and the quenching rates of the crystal are calculated after crystal growth and post growth quenching. One or more post growth process parameters are modified and programmed for subsequent crystal growth and post growth quenching to achieve optimized quenching rate and crystal quality.

Method to monitor and control the crystal cooling or quenching rate by measuring crystal surface temperature

A crystal puller and method for growing monocrystalline silicon ingots includes first and second electrical resistance heaters in the crystal puller in longitudinal, closely spaced relationship with each other to radiate heat toward the ingot as the ingot is pulled upward within the housing. In one embodiment, the first heater is powered when the ingot is pulled upward to a first axial position above the surface of the molten silicon and the second heater is powered when the ingot is pulled upward to a second axial position above the first axial position. In another embodiment the first and second heaters are powered until the ingot is separated from the molten silicon and then the heating power output of the first and second heaters is reduced to substantially increase the cooling rate at which the ingot is cooled. An adapter mounting the heaters may also be provided for adapting existing crystal pullers to incorporate the heaters.

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St. Charles, MO, United States of America

Zheng Lu