diff --git a/SiC/Surface Acoustic Wave (SAW) Sensors: Physics, Materials, and Applications.md b/SiC/Surface Acoustic Wave (SAW) Sensors: Physics, Materials, and Applications.md
new file mode 100644
index 0000000..60beb5e
--- /dev/null
+++ b/SiC/Surface Acoustic Wave (SAW) Sensors: Physics, Materials, and Applications.md	
@@ -0,0 +1,105 @@
+$\require{physics}$
+
+# Abstract
+
+声表面波就是在表面传播、波矢在面内的波。
+通常使用两个叉指电极（interdigitated electrodes，IDT），通过正向和逆向的压电效应，在一个电极上产生声表面波，经过介质传播，另一个电极上产生电压信号。
+一些需要测量的属性（例如温度）会影响声表面波的性质，从而被检测出来。
+
+图片来自维基百科。
+
+![undefined](assets/SAW_device.png)
+
+# Introduction
+
+这些微型的传感器（sensor）和执行器（actuator）被称为微机电系统（Microelectromechanical Systems, MEMS）。
+对于生物传感的方面，The devices have the potential to transform a complete wet laboratory into a tiny, miniaturized chip.
+
+One of the major limitations comes from the requirements of simultaneous sensing and the actuation in an environment
+  while engaging with mutually exclusive physics and mechanisms.
+
+为了解决这些问题，基于声表面波的传感器被提出来了，它们可以同时进行传感和执行。
+这些器件通常被称为 SAW sensors 或者 SAW devices，但它的功能不局限于传感和执行，还包括 filters, oscillators, transformers, etc.
+
+电到声的转换叫 actuation，声到电的转换叫 sensing。
+
+SAW sensor 用到了非常多的领域。
+
+The acoustic devices are responsive to the physical parameters of the species
+  that interact with the mechanical properties of the guided waves in the SAW sensors.
+
+总结来说，要探测的物理参数包括：mass, density, viscosity, elastic modulus, conductivity, temperature, and pressure.
+
+通常来说，可以通过检测波的传播速度来检测需要的物理参数。按照线性近似可以得到：
+
+$$
+\dd{V} = \pdv{V}{m}\dd{m} + \pdv{V}{E}\dd{E} + \pdv{V}{M_i}\dd{M_i} + \pdv{V}{e_v}\dd{e_v}
+$$
+
+但仅仅通过速度，是无法区分这些量导致的变化的，因此需要更多的信息，常用的包括：
+* the change in amplitude of the central frequency
+* the frequency shift of the given frequency input,
+* kurtosis
+* change in phase
+* higher-order frequency peaks to measure nonlinearity
+
+SAW sensor 的质量可以通过 sensitivity 和 selectivity 来衡量。
+Sensitivity 是指对于某个物理参数的响应程度（而不是直接对测得的电流或电压等的响应程度）。
+以受主和受体的结合为例子，sensitivity 是指多少受主被结合就可以检测出来，而 selectivity 是指其它不是目标的受主的出现是否会影响检测结果。
+
+# Types of Waves in SAW Devices
+
+## Rayleigh Waves
+
+瑞丽波的波矢在面内，由纵波和 shear vertical 模式组成，原子运动轨迹是椭圆形的。仅仅存在于表面，有效深度通常小于波长。
+地震波在远离震源的地表传播时，就是瑞丽波。
+
+![image-20240104230226306](assets/image-20240104230226306.png)
+
+#TODO: 更详细的性质
+
+## Shear Horizontal Waves
+
+波矢量在面内，原子运动轨迹垂直于波矢且在面内。
+可以深入材料大约几个波长的深度，在生物化学传感中有广泛应用，特别适合用于液体中。还有许多其它优点。
+
+#TODO: 更多优点
+
+通常会使用一个 guiding layer 来优化器件的性能，这个 guiding layer 可以使用 SiO2, Si3N4, 和其它多晶材料。
+
+#TODO: 更多理论
+
+![image-20240105112520807](assets/image-20240105112520807.png)
+
+## Lamb Waves
+
+兰姆波穿透整个材料，相当于将薄膜层作为了一个波导。它分为对称和反对称两种，乍一看有点类似光学的平板波导，只不过这个是机械波。
+
+![image-20240105113056845](assets/image-20240105113056845.png)
+
+#TODO: 更详细的理论
+
+## Love Waves
+
+在一种介质（薄膜）中传播时可以穿透整个材料（类似于 SH 波），而在另一种介质中传播时只能在表面传播（类似于瑞利波）。
+
+![image-20240105113614509](assets/image-20240105113614509.png)
+
+#TODO: 更详细的理论
+
+# Materials for the SAW Devices
+
+#TODO
+
+
+# Configuration of the Interdigitated Electrodes in the SAW Devices
+
+#TODO
+
+# SAW Applications
+
+#TODO
+
+# Conclusions
+
+#TODO
\ No newline at end of file
diff --git a/SiC/Surface Acoustic Wave (SAW) Sensors: Physics, Materials, and Applications.pdf b/SiC/Surface Acoustic Wave (SAW) Sensors: Physics, Materials, and Applications.pdf
new file mode 100644
index 0000000..6794cfc
--- /dev/null
+++ b/SiC/Surface Acoustic Wave (SAW) Sensors: Physics, Materials, and Applications.pdf	
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:7d59f0492ddcf3ff068417f99d22c8b8fd784497d17d0b64e9b3a07555a36614
+size 12837781
diff --git a/SiC/assets/SAW_device.png b/SiC/assets/SAW_device.png
new file mode 100644
index 0000000..cfe0672
--- /dev/null
+++ b/SiC/assets/SAW_device.png
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:95fb7684ad0b8b56f007598ba4f72f9f61a59b93ac4c8c53a999533d1d2db0b3
+size 1733
diff --git a/SiC/assets/image-20240104230226306.png b/SiC/assets/image-20240104230226306.png
new file mode 100644
index 0000000..6a636b5
--- /dev/null
+++ b/SiC/assets/image-20240104230226306.png
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:38833ee0dc689c792a88d30b00d735b00a5ba4f476bb3d232bcde8feea29c938
+size 168873
diff --git a/SiC/assets/image-20240105112520807.png b/SiC/assets/image-20240105112520807.png
new file mode 100644
index 0000000..d6ac427
--- /dev/null
+++ b/SiC/assets/image-20240105112520807.png
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:c99a5d8f0a9eb0fa285c06b2798f788978bf659698f5e70f8b1fa679d9790c2a
+size 54774
diff --git a/SiC/assets/image-20240105113056845.png b/SiC/assets/image-20240105113056845.png
new file mode 100644
index 0000000..8cea91f
--- /dev/null
+++ b/SiC/assets/image-20240105113056845.png
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:305ee85681d683c88879bf275e8e1fa617a4ce41a306baca5974d82ed899c388
+size 133336
diff --git a/SiC/assets/image-20240105113614509.png b/SiC/assets/image-20240105113614509.png
new file mode 100644
index 0000000..4d34c7b
--- /dev/null
+++ b/SiC/assets/image-20240105113614509.png
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:82eb24eb0718f6da2e13f0058d567681a573789c53d7e8f70b5c79ffc695a1b3
+size 81550
diff --git a/SiC/assets/image-20240105113734393.png b/SiC/assets/image-20240105113734393.png
new file mode 100644
index 0000000..cd7512b
--- /dev/null
+++ b/SiC/assets/image-20240105113734393.png
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:97cab4303676afa7f8c557cb574719ed7cd0956d0d0578766a2cc93e85829435
+size 441612