Research of the in-situ temperature measurement system for silicon wafers.

项目期间开展了以下3个研究项目。对每一项研究成果进行了简要描述。(1)混合型表面温度传感器。混合型表面温度传感器结合了接触式和非接触式测量方法的优点，并提供了一种克服接触式和非接触式测量方法缺点的方法。这种传感器实际上是一种改进的辐射温度计，可以进行无发射率的测量。在热稳态条件下，系统误差在0.5 K以内，在900 ~ 1000 K温度范围内随机误差在10.5 K以内。然而，它需要几十秒才能达到热稳态条件。这与原位测量应用相去甚远。新开发的快速响应混合型表面温度传感器利用了瞬态传热响应，其响应时间为1s。在相同的温度范围内，使用该传感器可以在±1k内测量温度。这种传感器有潜力用于校准原位温度测量，特别是在半导体行业。(2)利用高温下的偏振辐射进行辐射测温。本文从热辐射的光谱、方向和偏振特性等方面对中高温（900 K以上）下硅片的发射率进行了实验研究。通过实验验证了模拟模型估计的p、s极化辐射比与极化发射率之间的直接关系。该方法还具有半导体工业原位应用的潜力。(3)发射率不变条件。实验证实了这一发现对某些硅片是有效的。这一发现对工艺现场温度测量具有重要意义。为了充分证实这一条件的有效性，需要进一步深入研究。

The following 3 research items were carried out during the term of the project. Each research result is briefly described.(1) Hybrid-type surface temperature sensor.The hybrid-type surface temperature sensor combines the advantages of contact and non-contact methods and offers a way of overcoming the weak points of both methods. This sensor is actually a modified radiation thermometer that can conduct an emissivity free measurement. Under thermally steady state conditions, it can be concluded that the systematic error is-0.5 K, and the random error is within 10.5 K in the 900 to 1000 K temperature range. However, it takes several tens of seconds to reach thermally steady state conditions. This is far from an in situ measurement application. Instead, the transient heat transfer response was utilized by a newly developed rapid response hybrid-type surface temperature sensor that has a 1 s response time. A temperature measurement with this sensor is possible within ±1 K over the same temperature range. This sensor has the potential for use in calibrations of in situ temperature measurements, especially in the semiconductor industry.(2) Radiation thermometry by use of polarized radiances at high temperature.The emissivity of a silicon wafer has experimentally been investigated at a moderately high temperature (above 900 K) from the viewpoint of spectral, directional, and polarization characteristics of thermal radiation. The direct relationship between the ratio of p-and s-polarized radiance and polarized emissivity, as estimated by a simulation model, was confirmed experimentally. The method has also the potential for an in situ application for the semiconductor industry.(3) Emissivity-invariant condition.This finding was experimentally confirmed to be valid for some silicon wafers. This finding is very important for process in situ temperature measurement. Further intensive study is necessary to fully confirm the validity of this condition.