The Chemputronium 1S1R primitive is a repeatable building block that combines two functions into one cell:

• 1S (Selector): a rectifying element that preferentially conducts in one direction

• 1R (Resistive element): a one-time programmable (WORM) resistive path whose state can be permanently changed

 

When many 1S1R primitives are repeated in a grid, customers can assemble arrays, tiles, and custom circuits using standard row and column routing on a PCB.

 

What “1S1R” Means

1S1R stands for:

• One Selector (S): helps control current flow through a single cell in a matrix environment

• One Resistor (R): stores a programmable electrical state in the cell

 

In practice, the selector and resistive element are connected in series so current must pass through both.

 

What It Looks Like

A 1S1R primitive is typically implemented as a small overlap region between two conductors:

• A bottom electrode trace (row line)

• A top electrode trace (column line)

• A patterned Chemputronium™ stack in the overlap area that forms the selector and resistive element

 

From above, it resembles a compact “pixel” at the intersection of a row and a column. From the side, it is a thin functional stack bonded to the PCB surface and then optionally sealed with a protective cap layer.

 

How It Is Made

Chemputronium is used as a photopatternable functional material system that can be deposited and cured on PCB substrates to form the active region of each cell.

 

A typical build sequence is:

1. PCB base and electrodes
   The PCB is fabricated with defined copper traces for rows and columns and the required overlap geometry for each cell.

2. Surface preparation
   The overlap region is cleaned and prepared to improve adhesion and ensure consistent electrical interfaces.

3. Deposition
   Chemputronium is deposited onto the active overlap regions using PCB-compatible methods (for example stencil, screen, or controlled dispense, depending on customer process).

4. Photopatterning and curing
   The deposited material is cured to form a stable, solid functional structure. Photopatterning can be used to localize the material to the cell footprint and maintain clean boundaries between adjacent primitives.

5. Top electrode completion
   The top electrode trace completes the row/column intersection so the final cell is electrically addressable.

6. Optional encapsulation
   A protective coating can be applied to improve handling robustness and environmental stability, while keeping the cell electrically accessible through the row and column traces.

 

How Chemputronium Creates the Function

Chemputronium is engineered so that the 1S1R primitive exhibits two distinct regimes:

• Read regime: low-energy bias where the cell can be measured repeatedly

• Program regime: a higher energy bias condition that can permanently change the resistive element state

 

The selector behavior enables directional conduction and can help reduce unintended current paths when customers replicate cells into denser arrays. The resistive element provides a programmable state that can be set once and then read many times afterward.

 

Why This Primitive Matters

A 1S1R primitive allows customers to design their own structures while starting from a known, repeatable cell:

• Arrays for experimental compute-in-memory behavior

• Programmable threshold and quantization tiles

• OTP memory fields and configuration banks

• Programmable routing links and matrix-selected interconnect tiles

• Device-unique response mapping and characterization workflows

 

Important Note

Azoulaye Synapse supplies Chemputronium as a materials and process offering, along with reference documentation describing the 1S1R primitive.

 

Customers define their own end architectures, validation methods, and use cases. This page describes the primitive as a general building block and does not represent an end product implementation or guarantee application-specific outcomes.