摘要:
Heating element assemblies, heating furnaces incorporating heating element assemblies, methods to form heating element assemblies, methods to form heating furnaces and methods to reduce a magnetic field in a bifilar coil are disclosed. The heating element assembly includes two components, each component formed from heating element wire. The two components are spatially positioned and electrically arranged, relative to each other, so that an electrical current applied to the heating element assembly simultaneously travels through the two components in opposite directions.
摘要:
The present invention is a method and apparatus for calibrating a temperature feedback value in a wafer processing chamber to automatically compensate for variations in infrared emissions from a heated semiconductor wafer due to variations in composition and coatings from wafer to wafer. A calibration wafer with an imbedded thermocouple is used to generate a table relating actual wafer temperatures to power supplied to the heating chamber and infrared emissions detected by a pyrometer. A sample wafer of a batch to be processed is subsequently placed in the chamber at a known power level, and any difference between the detected infrared emission value and the value in the table is used to adjust the entire table according to a first predetermined formula or table. Before each wafer is processed, a known source of infrared light is reflected off the wafer and detected. The reflected light value is compared to a reflection measurement for the sample wafer. The difference in reflection measurements is correlated to emissions from heating, and the calibration table is fine-tuned with the correlation value according to a second predetermined formula or table to account for variations in emissions between individual wafers due to variances in wafer surface conditions.
摘要:
A low pressure control system for chemical vapor deposition (CVD) apparatus, including a vacuum pressure chamber and an exhaust pump, is provided by a vacuum pump DC motor which is supplied power from a DC motor speed controller coupled to a DC control input signal from a pulsewidth modulation DC converter. The converter receives a single pulsewidth modulated pulse train having its percentage of modulation controlled in accordance with a DC to pulsewidth modulation controller which operates in accordance with the difference between a pair of DC input signals corresponding to the actual pressure inside the vacuum pressure chamber and a desired or set point pressure respectively. The vacuum pump motor speed and accordingly the exhaust pump is controlled with a high degree of precision, thereby providing improved coating uniformity of semiconductor wafers being fabricated by the CVD apparatus.
摘要:
A circuit is provided that provides for the same power characteristics to an assembly of electrical resistive elements wired in parallel as to the assembly as wired in series. An input power source provides electrical resistive power to a plurality of load elements, wherein the plurality of load elements are connected in parallel to each other. A plurality of power splitters divide the power source into separate and equal power subsources such that there is one power splitter and one power subsource for each load element, wherein the power provided to each of the plurality of load elements is equal to the power of the electrical power source. Redundancy and fault tolerance is provided to the circuitry by permitting remaining load elements to continue to operate should one or more load elements fail.
摘要:
A method for monitoring the condition of a heating element involving installing the heating element in a location and setting the initial composition Ci of the material as a reference baseline at an initial time Ti corresponding to said installation of the heating element. Data is then collected reflecting the subsequent composition Cs of the heating element material after a subsequent time Ts at the installed location and any change in the material composition of the heating element between Ti and Ts is monitored. An alarm is sent when the change reaches a threshold value indicating a possible failure condition. According to one embodiment, an impedance monitor is provided that calculates and compares impedance at the required levels of accuracy to determine changes in material composition. The impedance monitor, or portions thereof can be embedded within a microcontroller for increased portability and functionality.
摘要翻译:一种用于监测加热元件的状态的方法,包括将加热元件安装在位置,并将材料的初始组成C i i i i i在初始时间T i i / SUB>对应于加热元件的所述安装。 然后在安装的位置的随后的时间T s之后收集反映加热元件材料的后续组成C'S的数据,并且加热元件的材料组成的任何变化 在T< I>和T SUB之间进行监视。 当变化达到指示可能的故障条件的阈值时发送报警。 根据一个实施例,提供阻抗监视器,其计算并比较所需精度水平处的阻抗以确定材料组成的变化。 阻抗监视器或其部分可以嵌入在微控制器内以增加便携性和功能性。
摘要:
The present invention is an apparatus for calibrating a temperature feedback value in a water processing chamber to automatically compensate for variations in infrared emissions from a heated semiconductor wafer due to variations in composition and coatings from wafer to wafer. A calibration wafer with an imbedded thermocouple is used to generate a table relating actual wafer temperatures to power supplied to the heating chamber and infrared emissions detected by a pyrometer. A sample wafer of a batch to be processed is subsequently placed in the chamber at a known power level, and any difference between the detected infrared emission value and the value in the table is used to adjust the entire table according to a first predetermined formula or table. Before each wafer is processed, a known source of infrared light is reflected off the wafer and detected. The reflected light value is compared to a reflection measurement for the sample wafer. The difference in reflection measurements is correlated to emissions from heating, and the calibration table is fine-tuned with the correlation value according to a second predetermined formula or table to account for variations in emissions between individual wafers due to variances in wafer surface conditions.
摘要:
A method for monitoring the condition of an electric current-carrying heating element involving installing the heating element in a location and setting the initial composition Ci of the material as a reference baseline at an initial time Ti corresponding to said installation of the heating element. Data is then collected reflecting the subsequent composition Cs of the heating element material after a subsequent time Ts at the installed location and any change in the material composition of the heating element between Ti and Ts is monitored. An alarm is sent when the change reaches a threshold value indicating a possible failure condition. According to one embodiment, an impedance monitor is provided that calculates and compares impedance at the required levels of accuracy to determine changes in material composition. The impedance monitor, or portions thereof may be embedded within a microcontroller for increased portability and functionality.
摘要翻译:一种用于监视载流加热元件的状态的方法,包括将加热元件安装在一个位置,并将材料的初始组成C i i i N在初始时间T i SUB>对应于所述加热元件的安装。 然后在安装的位置的随后的时间T s之后收集反映加热元件材料的后续组成C'S的数据,并且加热元件的材料组成的任何变化 在T< I>和T SUB之间进行监视。 当变化达到指示可能的故障条件的阈值时发送报警。 根据一个实施例,提供阻抗监视器,其计算并比较所需精度水平处的阻抗以确定材料组成的变化。 阻抗监视器或其部分可以嵌入在微控制器内以增加便携性和功能性。