Here is the announcement of Arm contributing a vendor-neutral version of the Arm Chiplet System Architecture (CSA), known as Foundation Chiplet System Architecture (FCSA), to the Open Compute Project (OCP) under their permissive open licensing policy. 

Accelerating an Open Chiplet Ecosystem for Automotive with Foundation Chiplet System Architecture  - Arm Newsroom

Happy to hear any comments from people.

In this publication MIT discuss work on RF GaN-on-Si Dielets Embedded in Glass Interposer to develop an advanced packaging technique for embedding of GaN HEMT dielets into glass interposers. A cavity is created in the glass interposer into which the GaN device is placed. A 2 layer RDL is then fabricated to connect the device. While there are still issues that need to be addressed it shows the buildup of RF circuits utilising singulated GaN dielets.

Silvaco TCAD, Keysight ADS, and Ansys HFSS were used for co-design of the GaN dielet in glass interposer circuit design and layout.

This white paper from IPDiA in France shows an example of an interposer with integrated passive devices for a medical sensor module including RF communication used in an implantable defibrillation system. It shows a significant size reduction and decreased weight of the total system.

In this video on the Video on Foundation Chiplet System Architecture, Mark Knight of Arm explains the difference between the FCSA (Foundation) and the Arm CSA. Basically anything in the Arm created CSA that is Instruction Set Architecture neutral is being defined in a new open standard the FCSA such that the Arm CSA will inherit from the FCSA and extend it with only those things that are Arm ISA specific. This should allow the creation of many chiplets that are agnostic to the compute systems ISA and can interoperate with any compute die that is certified by the FCSA.