z***3 发帖数: 496 | 1 请教一下关于raman的depth profiling
实验室用的是共焦显微拉曼,想给样品做depth profiling(深度剖析)。就是把焦点
放在样品不同的厚度上,然后比较各样品层的谱图。
一般是通过调节显微镜的上下移动旋钮去调节焦点,虽然旋钮上有刻度, 可问题是
怎么才能知道,旋几格刻度就是焦点移动了2微米,旋几格刻度就是焦点移动了5微米
呢? 有什么实验可以验证呢?
非常感谢
(不好意思,已经修改,应该是微米) |
v*****s 发帖数: 20290 | 2 这个好像和拉曼没什么关系啊。你找个已知厚度的玻璃片,然后转旋扭分别聚焦在上下
表面,看一下刻度差不就知道了。
【在 z***3 的大作中提到】![](/moin_static193/solenoid/img/up.png) : 请教一下关于raman的depth profiling : 实验室用的是共焦显微拉曼,想给样品做depth profiling(深度剖析)。就是把焦点 : 放在样品不同的厚度上,然后比较各样品层的谱图。 : 一般是通过调节显微镜的上下移动旋钮去调节焦点,虽然旋钮上有刻度, 可问题是 : 怎么才能知道,旋几格刻度就是焦点移动了2微米,旋几格刻度就是焦点移动了5微米 : 呢? 有什么实验可以验证呢? : 非常感谢 : (不好意思,已经修改,应该是微米)
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z***3 发帖数: 496 | 3 谢谢斑竹回复
因为玻璃会折射光线,表面上看到是聚焦到玻璃下表面,但移动的距离可能跟厚度不一致
而且实验的时候是每几微米就要做一个图,对精度要求不低 |
x*******i 发帖数: 32 | 4 You are using a home-made Raman instrument right? For confocal Raman
instruments from major vendors, you do not need to consider how to measure
the distance of the focus movement, because it is controlled by stage with
spatial resolution of 100 nm (normal type) or 10 nm (advanced type).
I need some time to think about how to answer your question. But confocal
Raman experiment may not be able to determine the thickness by the technique
itself on the well-known sample, because the refractive index mismatching
on the interface causes defocusing into the sample. The simplest although
not very accurate correction is obtained by dividing the real thickness by
RI of your sample. There are extensive publications in Applied Spectroscopy
in this topic. The only exception to obtain accurate answer is to use
refractive index matching liquid to make sure the RI of the sample and
medium for the light pass is same.
【在 z***3 的大作中提到】![](/moin_static193/solenoid/img/up.png) : 请教一下关于raman的depth profiling : 实验室用的是共焦显微拉曼,想给样品做depth profiling(深度剖析)。就是把焦点 : 放在样品不同的厚度上,然后比较各样品层的谱图。 : 一般是通过调节显微镜的上下移动旋钮去调节焦点,虽然旋钮上有刻度, 可问题是 : 怎么才能知道,旋几格刻度就是焦点移动了2微米,旋几格刻度就是焦点移动了5微米 : 呢? 有什么实验可以验证呢? : 非常感谢 : (不好意思,已经修改,应该是微米)
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z***3 发帖数: 496 | 5 非常感谢xiaoyazhi 的信息
我们的如拉曼不是home-made
是HORIBA的 HR800 |
x*******i 发帖数: 32 | 6 Then there is no need for you to worry about movement of the focus. You can
control the focus movement of the stage using software. If you are using oil
immersion objective or water immersion/dipping objective, the stage
movement is equal to the focus movement. Otherwise if you are using a dry
objective, the stage movement is smaller than the real thickness roughly by
a factor of refractive index. One of the first papers to discuss this
artifact is Applied spectroscopy 2000, 54, 773. I remember this author also
collaborated with Fran Adar, Global Application Manager of Raman
spectroscopy at Horiba, to publish the artifacts around 2005 in Applied
Spectroscopy.
【在 z***3 的大作中提到】![](/moin_static193/solenoid/img/up.png) : 请教一下关于raman的depth profiling : 实验室用的是共焦显微拉曼,想给样品做depth profiling(深度剖析)。就是把焦点 : 放在样品不同的厚度上,然后比较各样品层的谱图。 : 一般是通过调节显微镜的上下移动旋钮去调节焦点,虽然旋钮上有刻度, 可问题是 : 怎么才能知道,旋几格刻度就是焦点移动了2微米,旋几格刻度就是焦点移动了5微米 : 呢? 有什么实验可以验证呢? : 非常感谢 : (不好意思,已经修改,应该是微米)
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y****i 发帖数: 1504 | 7 这种validation的问题为啥不问仪器公司的technique support? |
f***a 发帖数: 11477 | 8 你没有微动平台吗?
一般显徴拉曼都有3维平台。
数字输入z轴移动量。还可以连续扫描拍movie |
f***a 发帖数: 11477 | 9 你忽略了介面放大,用平均太不准。
有专门的厚度深度测量仪。
或者afm挖坑测。
或者做成pattern测高度差,更准一些。
【在 x*******i 的大作中提到】![](/moin_static193/solenoid/img/up.png) : You are using a home-made Raman instrument right? For confocal Raman : instruments from major vendors, you do not need to consider how to measure : the distance of the focus movement, because it is controlled by stage with : spatial resolution of 100 nm (normal type) or 10 nm (advanced type). : I need some time to think about how to answer your question. But confocal : Raman experiment may not be able to determine the thickness by the technique : itself on the well-known sample, because the refractive index mismatching : on the interface causes defocusing into the sample. The simplest although : not very accurate correction is obtained by dividing the real thickness by : RI of your sample. There are extensive publications in Applied Spectroscopy
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f***a 发帖数: 11477 | 10 原来你是做深度剖析,那么微动平台纵向移动距离不一定等于实际焦点移动距,介质的
各种光学指数都会影响这个差值。
你可以理论粗略较正,或者类似生物作切片,微切下来一部分,放平,变z方向为xy方
向,作水平扫描。当然,得到数据需要矩阵变化一下,依赖于你样品的对称点群和切割
角度。 |
y***n 发帖数: 11261 | 11 赞
【在 f***a 的大作中提到】![](/moin_static193/solenoid/img/up.png) : 原来你是做深度剖析,那么微动平台纵向移动距离不一定等于实际焦点移动距,介质的 : 各种光学指数都会影响这个差值。 : 你可以理论粗略较正,或者类似生物作切片,微切下来一部分,放平,变z方向为xy方 : 向,作水平扫描。当然,得到数据需要矩阵变化一下,依赖于你样品的对称点群和切割 : 角度。
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