Substrates for Anisotropic Etching

university wafer substrates

100mm Silicon Wafers Used for KOH Anisotropic Etching

A PhD candidate requested the following quote:

Please quote the following:

100mm N/Ph (100) >10,000 ohm-cm SSP

This is used for KOH anisotropic etching. So the flats need to be aligned with the 110 direction. Resistivity should ideally be high (non-conductor) but is not critical.

Reference #96584 for specs and pricing.

Get Your Quote FAST! Or, Buy Online and Start Researching Today!





CAPTCHA Image

Thermal Oxide Wafers for Anisotropic Etching

A assistant professor requested the following quote:

I need a quote for 4" (100mm) Si wafers. Thickness 525 +-25 micron (100) Orientation in prime quality for anisotropic etching. The wafers should be DSP with a thermal oxide of 2 - 3 micron.

We`ll use the wafers for scientific purposes.

Reference #234/3229397 for specs and pricing.

 

What is Anisotropic Etching?

Anisotropic etching is a process used in microfabrication to create well-defined patterns on a material, typically a semiconductor like silicon. The key feature of anisotropic etching is that it etches at different rates in different directions. This directional dependence allows for the creation of very precise and sharp features with high aspect ratios (the ratio of depth to width in the etched features).

In contrast to isotropic etching, which etches uniformly in all directions, anisotropic etching can be controlled to etch faster in one direction. This is particularly useful in semiconductor manufacturing, where it's essential to create intricate and precise microstructures.

There are several methods of achieving anisotropic etching, including:

  1. Wet Chemical Etching: Uses specific chemical solutions that etch certain crystal planes of a material faster than others. This method is often used in silicon microfabrication, as silicon has different etch rates depending on its crystal orientation.

  2. Dry Etching: Involves the use of gases or plasmas to etch the material. Dry etching techniques, such as reactive ion etching (RIE), are highly anisotropic and can create very fine and precise features.

Anisotropic etching is vital in various applications such as the fabrication of microelectromechanical systems (MEMS), integrated circuits, and various nanotechnology applications. The ability to control the etching process with high precision allows for the creation of complex and miniaturized components that are essential in modern electronics and technology.

What Substrates Are Commonly Used For Anisotropic Etching Include?

  1. Silicon: Silicon is the most widely used substrate in anisotropic etching, especially in semiconductor manufacturing. It's favored for its mechanical properties, availability, and the well-understood etching behavior. Silicon's ordered atomic lattice is key for finely carving along certain crystal directions, which is pivotal in crafting the tiny, complex parts essential to microtechnology.

  2. Glass and Quartz: These bases are favored for tasks that demand a clear view or certain heat-handling characteristics. Anisotropic etching of glass and quartz is often achieved using techniques like reactive ion etching (RIE) to create microfluidic devices and optical components.

  3. Sapphire: Sapphire is another substrate used for anisotropic etching, particularly for its high mechanical strength and thermal stability. Sapphire's ability to stand up to extreme heat makes it a go-to choice in industries like LED production, where materials must endure high temperatures.

  4. Gallium Arsenide (GaAs): This is a compound semiconductor used in high-frequency and optoelectronic applications. Anisotropic etching of GaAs allows for the creation of devices like microwave components and laser diodes.

  5. Silicon carbide (SiC): with its high thermal conductivity and electrical resistance, finds use in power devices and applications requiring high temperatures. Silicon carbide, known for having both high thermal conductivity and electrical resistance, finds use in power devices and applications requiring high temperatures. Sculpting SiC with directional precision is essential for forging devices that remain steadfast under the ruthless demands of extreme heat and power.

The choice of substrate often depends on the intended application of the etched component. When picking out a base for etching, it's not just about how tough or heat-proof the material is; we also consider its atomic makeup and whether it can handle chemicals without falling apart, all to make sure it does the job right when crafting tiny but crucial parts for gadgets and machines. By carving out tiny and even tinier shapes with great accuracy, anisotropic etching crafts essential components for cutting-edge gadgets in electronics, light-based tech, and the tiny machines within MEMS.