Company Blog

Measuring the I-V Characteristic of PN Junction Devices with the HF2LI

13.05.2015

Co-author and main contributor: Dr. Antonio Braga Introduction The p-n junction is the fundamental building block of semiconductor material electronics device such as transistors, diodes, sensors, laser, light emitting diodes, as well as solar cells. If one wants to know the fundamental functional properties of these devices, it is crucial...

DFRT-PFM Workshop

27.11.2014

Earlier in November 2014, Zurich Instruments participated in a 2-day workshop on Piezoresponse Force Microscopy (PFM) organized by the Institut des Nanotechnologies de Lyon (INL) and the CNRS network RéMiSoL (Réseau des Microscopies à Sondes Locales). Starting with some theoretical introduction by Prof Brice Gautier, 2 parallel sessions on practical...

Demodulating Down to DC with the HF2LI

18.11.2014

Many of our customers use the possibility to measure DC voltage and current, together with an ac signal by setting the demodulation frequency ω=0. The measured value is seemingly incorrect as you need to divide the obtained rms value with the factor of √2 to get the actual signal amplitude...

Using Vertical Axis Groups to Plot Signals of Different Scales or Units

13.10.2014

LabOne ® offers a flexible display of multiple signal waves within the same plot. This blog post describes the functionality of the vertical axis groups, which make it possible to finely control how signals are bound together within the plot. Vertical axis groups are available in the Plotter tab, SW...

Detecting a Small Fraction of Impedance Changes with Improved Sensitivity

16.09.2014

Basic Vector Network Analyzer Measurements with the UHFLI

03.07.2014

Introduction This blog post describes how to measure reflection and transmission coefficients using the Zurich Instruments UHFLI Lock-in Amplifier and a directional coupler. Network analysis is commonly performed in radiofrequency (RF) measurements. A network analyzer is an instrument that measures the network parameters of electrical circuits. Circuits that can be...

How to Achieve More Stable Z-feedback in FM-AFM Mode

15.05.2014

The challenge with FM-AFM mode (or NC-AFM) is that tip-sample interaction can be either attractive (negative frequency shift, -df) or repulsive (positive frequency shift, +df) which leads to different parameter settings for the Z feedback loop with, respectively, either a positive or negative slope. For atomically smooth surfaces this is...

Sideband Analysis with Lock-in Amplifiers

27.02.2014

When a sinusoidal waveform is periodically modulated in either amplitude or frequency, sidebands are generated as a result of this carrier modulation. These sidebands can be measured using a lock-in amplifier. Zurich Instruments' lock-in amplifiers (such as the HF2LI and the UHFLI) can measure up to 8 frequencies simultaneously and...

Reducing Ground Disturbances with the HF2TA

26.02.2014

Ground loops can pose a serious problem in many measurement setups. Due to the multiple connections to and from the HF2TA Current Amplifier and other external components, several ground loop related issues can pop up in the signal being measured. These issues can be high-frequency oscillations (> 10 MHz), 50/60...

High-Speed AFM Measurements

19.02.2014

Typically, for biological and catalysis applications time matters - and AFM images recorded in 10 minutes or longer are not acceptable. We often receive inquiries about what constitutes a complete solution for 'fast AFM' and what Zurich Instruments can offer in this area. Therefore, I would like to describe here...

Taking Your Microfluidics EIS Measurement to the Ultra-High Frequency Domain

08.01.2014

Introduction The HF2IS Impedance Spectroscope from Zurich Instruments is a versatile tool suitable for label-free electrical impedance spectroscopy (EIS) of single cells in the domain of cell counting and discrimination. The high frequency range, from DC to 50 MHz, and the multi-frequency capability of the instrument enable microfluidics researchers not...

Ring-Down Method for Rapid Determination of High Q-Factor Resonators

18.12.2013

With the miniaturization of circuits and components such as MEMS and now also NEMS, the variety and quality of macro-fabricated devices have dramatically increased, leading to packaged or embedded systems with particularly sensitive electromechanical properties. The basic properties, such as resonance frequencies, Q-factor and dissipative power requires more and more...

GHz Differential Amplifier Using a 180° 2-Way Power Splitter

10.10.2013

Every now and then, a differential amplifier in the frequency range of the UHFLI Lock-in Amplifier is needed. The requirements for such an amplifier are low noise and a frequency range of at least 600 MHz. A commercial solution with an active differential amplifier is not available today. A straightforward...

How to Tune the HF2LI-PID Controllers

17.09.2013

I often get questions from first-time users on how to properly tune the PID gain parameters. I am no expert in feedback control systems or the PID loop optimization, but I do believe tuning the HF2LI-PID parameters should not be an intimidating task for anybody who needs to use the...

ダブルサイドバンド・サプレスドキャリア(DSB-SC, 搬送波抑圧両側波帯)変調

28.08.2013

ダブルサイドバンド・サプレスドキャリア (DSB-SC, 搬送波抑圧両側波帯) 変調は、対称的な2つのサイドバンドのみで構成され、搬送波がない振幅変調です。私は超音波のアプリケーションでこの方式に出会いましたが、サイドバンドにすべての電力を利用できるようにすると電力利用率が最大になります。HF2LI及びUHFLIのロックインアンプ搭載されているMODオプションを使えば、DSB-SC変調を簡単に生成・復調できます。MODオプションはZurich Instruments のロックインアンプ独自の機能で、与えられたキャリアと変調周波数に基づいて、サイドバンドの直接合成と復調を可能にします。重要なのは、指定するのはサイドバンドの周波数ではなく、中心及び搬送波と変調波の周波数（搬送波とサイドバンドの距離）であることです。このことは以下の様な極めて重要な意味を持ちます。 変調周波数を、ボード線図のように簡単に掃引することができます。 サイドバンドが同じ発振器で作られるので、2つのサイドバンド間の位相関係が常に一定に保つことができます。 搬送波周波数と変調周波数をPLLなどで制御した場合でも、位相関係が常に指定できます。 図1に示すように、波形の生成は簡単にできます。