Issue link: https://iconnect007.uberflip.com/i/1519075
APRIL 2024 I PCB007 MAGAZINE 9 Marcy LaRont is the editor of PCB007 Magazine. Marcy started her career in PCBs in 1993 and brings a wide array of business experience and perspective to I-Connect007. To contact Marcy , click here. more about IPC Validations Services, which, aer 11 years, has 140 companies able to ver- ify they meet or exceed the written IPC stan- dards. Finally, IPC's Joe O'Neil gives an impor- tant update on the U.S. Partnership for Assured Electronics (USPAE) research and develop- ment facility, the Printed Circuit Board Market Catalyst (PBMC)—what it is and what it will offer the PCB industry aer it's built. As usual, our columnists have shown up with force. Don Ball of Chemcut finishes his two-part series on reducing etch system water usage. Henry Crandall offers a compelling and personal column on the criticality of reliability in medical electronics as he takes us through the birth of his child and a malfunctioning sensor. Material scientist Preeya Kuray pro- vides an excellent discussion on Dk, and Happy Holden uses his Tech Talk series to finish his coverage of power mesh architecture. Last but not least, I know you'll find value in our new series of audio interviews enti- tled "Young Professionals," featuring the next- generation workforce in the varying areas of our industry who are crushing it. Workforce remains one of the biggest topics in our indus- try today, whether we are discussing work- force training, culture, or knowledge transfer. In this episode, you'll meet Jennifer Robinson of TTA. Finally, many of us are just arriving home aer a week in Anaheim at IPC A PEX E XPO 2024. It was a full week and I-Connect007 was there. Make sure to visit our video and photo site, realtimewith.com, to see what you may have missed; and stay tuned for our 2024 Show & Tell Magazine in a few weeks. And when you find something in this issue that resonates, please share it with your friends and colleagues. PCB007 Spectroscopy and Theory Shed Light on Excitons in Semiconductors From solar panels on our roofs to the new OLED TV screens, many everyday electronic devices simply wouldn't work without the inter- action between light and the materials that make up semiconductors. A new category of semi- conductors is based on organic molecules, which largely consist of carbon, such as buck- minsterfullerene. The way organic semiconduc- tors work is largely determined by their behav- iour in the first few moments after light excites electrons, forming "excitons" in the material. Researchers from the Universities of Göttin- gen, Graz, Kaiserslautern-Landau and Greno- ble-Alpes have now, for the first time, made very fast and very precise images of these excitons— in fact, accurate to one quadrillionth of a second (0.000,000,000,000,001s) and one billionth of a metre (0.000,000,001m). This understanding is essential for developing more efficient materials with organic semiconductors. The results were published in Nature Communications. When light hits a material, some electrons absorb the energy and this puts them into an excited state. In organic semiconductors, such as those used in OLEDs, the interaction between such excited electrons and left-over "holes" is very strong, and electrons and holes can no lon- ger be described as individual particles. Instead, negatively charged electrons and positively charged holes combine to form pairs, known as excitons. Understanding the quantum mechani- cal properties of these excitons in organic semi- conductors has long been considered a major challenge—both from a theoretical and an exper- imental point of view. (Source: University of Gottingen )