Flexible High Electron Mobility Transistor
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Integration of Compound Semiconductors on Flexible Substrates Terry L. Alford, Arizona State University, DMR 0902277 Flexible High Electron Mobility Transistor Recent work has been focused on the process of fabricating high electron mobility transistors on flexible substrates. We have developed an enabling process, using patterned ion-cutting, selective etching, and laser ablation to transfer InP-based modulation doped field effect transistors (MODFET) on flexible PEN substrates. First, selective hydrogen implantation was performed, with device areas protected by an ion mask. Following implantation and removal of the ion mask, the substrate is bonded to sapphire using the photoresist polymer SU-8. Pattern ion-cut is initiated, with 40% of the protected areas transferred along with the implanted regions. Chemical etching removes the selective etch stops, revealing the device layers ready for fabrication. Low temperature processing (150°C or less) completes the device transfer onto sapphire. To transfer onto flexible PEN substrate, the device structure is bonded to PEN Figure 1: Schematic of double-flip process for enabling flexible HEMT
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Integration of Compound Semiconductors on Flexible Substrates Terry L. Alford, Arizona State University, DMR 0902277. Flexible High Electron Mobility Transistor Recent work has been focused on the process of fabricating high electron mobility transistors on flexible substrates. - PowerPoint PPT Presentation
Transcript of Flexible High Electron Mobility Transistor
Integration of Compound Semiconductors on Flexible Substrates
Terry L. Alford, Arizona State University, DMR 0902277
Flexible High Electron Mobility Transistor
Recent work has been focused on the process of fabricating high electron mobility transistors on flexible substrates.
We have developed an enabling process, using patterned ion-cutting, selective etching, and laser ablation to transfer InP-based modulation doped field effect transistors (MODFET) on flexible PEN substrates. First, selective hydrogen implantation was performed, with device areas protected by an ion mask. Following implantation and removal of the ion mask, the substrate is bonded to sapphire using the photoresist polymer SU-8. Pattern ion-cut is initiated, with 40% of the protected areas transferred along with the implanted regions. Chemical etching removes the selective etch stops, revealing the device layers ready for fabrication. Low temperature processing (150°C or less) completes the device transfer onto sapphire. To transfer onto flexible PEN substrate, the device structure is bonded to PEN with SU-8, and a laser beam is sent through the sapphire substrate, delaminating the original SU-8 bonding layer. A plasma is used to remove residual SU-8 and complete the double-flip transfer onto flexible substrate.
Figure 1: Schematic of double-flip process for enabling flexible HEMT
Enabling high-speed flexible electronics
Transferred MODFETs on flexible substrates exhibited typical transistor behavior. Our devices were for demonstration of the enabling technology and so, long channel conventional fabrication techniques were used.DC measurements were used to characterize the mobility of the transferred FETs. From I-V and C-V data we extrapolated μelectron~2800cm2V-1s-1, which far exceeds any previously reported values for thin film transistors (TFT) on flexible substrate. We believe even higher performance is achievable through device and process optimization.
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Integration of Compound Semiconductors on Flexible Substrates
Terry L. Alford, Arizona State University, DMR 0902277
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Exploring Light and Photodetectors
With the assistance of Ms. Roxanna Montoya-Gonzales the initial demonstration/experiments for the PreK-K outreach activities were undertaken. Various sources of light and the concept of photodetectors will be presented to students at the Keys Center in Phoenix, AZ. This center has a large population of Latino students from low income areas. Most activities are hands on. Another aim is for none of these materials to be of “one-time use items;” hence, the modules will be sustainable.
Integration of Compound Semiconductors on Flexible Substrates
Terry L. Alford, Arizona State University, DMR 0902277
