LT-GaAsの

LT-GaAsの

我々は提供 LT-GaAsの wafer for THz, detector, ultra-fast-optical experiments and other applications.

1. 2インチLT-GaAsウェーハ仕様:

アイテム 仕様書
Diamater(ミリメートル) 1ミリメートル±Фの50.8ミリメートル
厚さ 1-2umまたは2-3um
マルコ欠陥密度 ≤5センチメートル-2
抵抗率(300K) > 108オームcm
キャリア <1ps
転位密度 <1×106cm-2
使用可能な表面積 ≥80%
研磨 片面研磨
基板 GaAs基板

 

備考:その他の条件:

1)GaAs基板は、(100)配向でドープされていない/半絶縁性である必要があります。
2)成長温度:〜200-250 C

2. LT-GaAsの紹介:

低温成長したGaAs は、光伝導性THzエミッターまたは検出器の製造に最も広く使用されている材料です。 そのユニークな特性は、優れたキャリア移動度、高い暗抵抗率、およびサブピコ秒のキャリア寿命です。

300°C(より低い温度で分子線エピタキシー(MBE)によって成長させたGaAsLTのGaAs) presents a 1%–2% arsenic excess which depends on the growth temperature Tgand on the arsenic pressure during the deposition. As a result a high density of arsenic antisite defects AsGa is produced and forms a donor miniband close to the center of the band gap. The concentration of AsGa increases with decreasing Tg and can reach 1019–1020 cm-3, which leads to a decrease of the resistivity due to hopping conduction. The concentration of ionized donors AsGa+, which are responsible for the fast electron trapping, depends strongly on the concentration of acceptors (gallium vacancies). The LT-MBE grow GaAs samples are then usually thermally annealed: The excess arsenic precipitates into metallic clusters surrounded by depleted regions of As/GaAs barriers which allow one to recover the high resistivity. The role of the precipitates in the fast carrier recombination process is, however, not yet completely clear. Recently, attempts have been made also to dope LT GaAs during the MBE growth with compensating acceptors, namely with Be, in order to increase the number of AsGa+ : the trapping time reduction was observed for heavily doped samples.

3. LT-GaAsテストレポート:

LT-GaAsのレポートを参照するには、以下をクリックしてください:

https://www.powerwaywafer.com/low-temperature-gaas-2.html

4.LT-GaAsでのTHz生成プロセス

https://www.powerwaywafer.com/THz-Generation-Process-in-LT-GaAs.html

5.テラヘルツ光伝導アンテナの性能:

この記事を参照するには、以下をクリックしてください:

https://www.powerwaywafer.com/performance-of-terahertz-photoconductor-antennas.html

6.THzの時間領域スペクトル

以下は、LT-GaAsウェーハから作成されたTHzの時間領域スペクトルです。

THzの時間領域スペクトル

THzの時間領域スペクトル 

 7.LT-GaAsウェーハの時間分解スペクトル

LT-GaAsウェーハの時間分解スペクトル

LT-GaAsウェーハの時間分解スペクトル

8. FAQ of LT-GaAs Wafer

Q1: Can LT-GaAs substrate be passivated? Does washing the surface with ultrasonics have any effect on that layer of low temperature GaAs?

The LT-GaAs substrate can do passivation treatment. It is no problem that wash the surface of LT-GaAs with low-power ultrasonic waves.

Q2: I do photolithography to deposit insulating layer, such as SiO2 100 nm, and metal electrode of Cr 10 nm/ Au 100 nm on LT-GaAs wafer. After the fabrication, I inject a pulsed laser to generate a pulsed charge current. This light-to-charge conversion is done at ambient air at room temperature. The device looks good initially, but after several usage the Au electrode part looks bumpy. (I checked it with a microscope.) I guess the bumpy shape is because water molecules that were unintentionally present in between GaAs and SiO2 or between SiO2 and Cr/Au evaporate by the laser-induced heating. Do have any idea to avoid this issue?

We haven’t met this situation before, you can bake the LT GaAs substrate before plating metal, but the temperature should be not too high, below 300 degrees. In addition, you need to rinse the film with dilute acid before making the metal process.

Q3: For low-temperature grown GaAs, we need to work under the scanning tunneling microscope, but the resistivity is too large to tunnel. So, is it possible to reduce the resistivity preferably to below 1M ohm/mm of the epitaxial layer (along the surface direction) by doping? There are no requirements for the elements to be doped and the method of doping.

The electrical resistivity of LT-GaAs epi thin film would be able to drop below 1M ohm/mm. Specific technology inquiries please contact victorchan@powerwaywafer.com.

9. Related Products:

LT用のGaAsウェハ
LT-GaAsの光伝導スイッチ
LT-GaAsのキャリア寿命
LT用のGaAsテラヘルツ
batopのLT-GaAsの

出典:PAM-厦門

powerwaywafer


For more information, please contact us email at victorchan@powerwaywafer.compowerwaymaterial@gmail.com.

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